For wire resistor flows current. Unspractified DC electrical circuit consists of a current source and an external resistor connected to its conclusions. How to change with a decrease in resistor resistance The power of the current in the chain and the EMF source

Question 17 on Demidova

Task 17. On a wire resistor flows current. The resistor was replaced on another, with a wire from the same metal and the same length, but having a smaller cross-sectional area, and they missed a smaller current through it. How do the voltage on the resistor and its resistance change?

1) increase

2) will decrease

3) will not change

Task 17. On a wire resistor flows current. The resistor was replaced on another, with a wire from the same metal and the same cross section, but twice as smaller length, and they missed the smaller current through it. How do the voltage on the resistor and its resistance change?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. Flat condenser With an air gap between the plates is connected to the source constant voltage. How will change when a reduction in the gap between the capacitor plays is electrostatura and the charge value on its plates? For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. A flat condenser with an air gap between the plates is connected to a constant voltage source. How will the field intensity change in the gap between the condenser's plates and the charge value on its plates, if you increase the gap between them?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. The charged particle mass M, moving at a speed V, flies in the field of a flat capacitor (see Figure). The distance between the capacitor plates is d, and the voltage of the electric field between the plates is equal to E. The condenser is flying, the particle deviates from the initial direction to the angle a.

How will the velocity module change the particle and angle A, if you reduce the magnitude of the electric fields between the condenser plates? For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. The charged particle mass M, moving at a speed V, flies in the field of a flat capacitor (see Figure). The distance between the plates of the capacitor is d, the length of the plates L \u003e\u003e D, and the magnitude of the electric field tension between the plates is equal to E. Flying the condenser, the particle deviates from the initial direction to the angle a.

How will the velocity module change the particle and angle A, if you increase the particle speed at the inlet to the condenser?

1) increase

2) will decrease

3) will not change

Task 17. The figure shows the chain direct currentcontaining the current source with EMF resistor R1 and R2 R2. If you reduce the resistance of R2 resistance to a minimum, then how the current is changed in the chain and the total thermal power released at the external section of the chain? Internal resistance of the current source neglected.

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. The figure shows a DC circuit containing a current source with EMF E and two resistors: R1 and R2. If the key to closes, then how the current is changed through the R1 resistor and the voltage on the R2 resistor? Internal resistance of the current source neglected.

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. Proton in a homogeneous magnetic field is moving around the circle. So that in this field moves around the circumference at the same speed of the A-particle, the circle radius and the frequency of the circulation of the A-particle compared to the proton should:

1) Enhance

2) decrease

3) not change

Task 17. Proton in a homogeneous magnetic field is moving around the circle. So that in this field moves around the circumference at the same speed of the A-particle, the centripetal acceleration of the A-particle and the period of its appeal compared to the proton should:

1) Enhance

2) decrease

3) not change

Task 17. Flat condenser charged and disconnected from galvanic element. How will change when a reduction in the gap between the capacitor plates capacitor capacitance and the charge value on its plates?

1) increase

2) will decrease

3) will not change

Task 17. Flat air capacitor with a dielectric between the plates is connected to the battery. Do not shut down the capacitor from the battery, the dielectric was removed from the condenser. How do the capacitance capacitance and the potential difference between its plates change?

1) increase

2) will decrease

3) will not change

Task 17. In the transparent vessel filled with water, there is a diffraction lattice. The lattice is illuminated by the beam of light laser pointer, falling perpendicular to its surface through the side wall of the vessel. How will the frequency of the light wave falling on the grille and the angle between the normal to the lattice and the direction on the first diffraction maximum when removing water from the vessel?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. In the transparent vessel filled with water, there is a diffraction lattice. The grille is illuminated by a parallel bunch of monochromatic light, falling perpendicular to its surface through the side wall of the vessel. How will the length of the light wave falling on the grid change, and the angle between the normal to the lattice and the direction on the first diffraction maximum when replacing water in the vessel with a transparent liquid with a large refractive index?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. Unswar electrical circuit Consists of a source of constant voltage and resistor. How to change with an increase in the internal resistance of the source the power of the current in the chain and voltage on the resistor? For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. The unbranched electrical circuit consists of a source of constant voltage and resistor. How will change with a decrease in the internal resistance of the source power released on the resistor and the electromotive power of the source?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. When adjusting the oscillatory loop of the radio transmitter, its inductance has decreased. How will the frequency of the emitted waves change and the radiation wavelength change?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. When setting the oscillatory loop of the radio transmitter, its inductance increased. How will the period of current fluctuations in the circuit and the wavelength of the electromagnetic radiation change?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. On a wire resistor flows current. How to change with a decrease in wire length 4 times and increasing the current strength by half the thermal power released on the resistor and its electrical resistance?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. On a wire resistor flows current. How to change with a decrease in wire length 2 times and increasing the current strength by half the thermal power released on the resistor and its electrical resistance?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. In the diagram shown in Figure, R1\u003e R2. What happens to the ammeter and voltmeter readings after switching the key to position 1 to position 2? For each value, determine the corresponding nature of its change:

1) increase

2) will decrease

3) will not change

Task 17. In the diagram shown in Figure, R1< R2. Что произойдёт с показаниями амперметра и вольтметра после переключения ключа К из положения 1 в положение 2? Для каждой величины определите соответствующий характер её изменения:

1) increase

2) will decrease

3) will not change

ancade 17. The student conducted experience in the refraction of the light, submitted in the figure. How to change when a decrease in the angle of incidence of the refractive area spreading in glass and the refractive index of glass?

1) increase

2) will decrease

3) will not change

Task 17. The student conducted experience in the refraction of the light, presented in the figure. How to change when angle increasing the angle of refraction of the light spreading in glass and the refractive index of glass?

1) increase

2) will decrease

3) will not change

Task 17. When adjusting the oscillatory loop of the radio transmitter, its inductance has decreased. How did the current fluctuations in the circuit and the radiation wavelength changed?

For each value, determine the corresponding nature of the change:

1) increased

2) decreased

3) has not changed

Task 17. When setting the oscillatory loop of the radio transmitter, the capacitance of the capacitor incoming in it increased. How did the current oscillation frequency in the circuit and the radiation wavelength changed?

For each value, determine the corresponding nature of the change:

1) increased

2) decreased

3) has not changed

Task 17. Proton in a homogeneous magnetic field is moving around the circle. How will the radius of the circle and the transaction period change, if its speed increase?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. Proton in a homogeneous magnetic field is moving around the circle. How will the radius of the circle and the transaction period change, if its speed decreases?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Task 17. The figure shows a DC circuit containing a current source with EMF E and two resistors: R1 and R2. If the key to close, then how the current is changed through the resistor and the total thermal power released at the external section of the chain? Internal resistance of the current source neglected.

1) increase

2) will decrease

3) will not change

Task 17. The figure shows a DC circuit containing a current source with EDC E and two resistors R1 and R2. Initially the key is closed. If the key to break, then how will the overall resistance of the external section of the chain and voltage on the R1 resistor change? Internal resistance of the current source neglected. For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

1 . A small object is located on the main optical axis of a thin collecting lens on a double focal length from it. The object is beginning to bring the focus of the lenses. How do the optical power of the lenses and image size change?

1) increases

2) decreases

3) does not change

Decision.

From the figure it is seen that when the object is approached to the focus of the lens (blue line), its image increases.

Answer: 31.

2. A small object is located on the main optical axis of a thin collecting lens on a triple focal length from her. The object is beginning to move away from the lenses. How do the optical power of the lenses and image size change?

For each value, determine the corresponding nature of its change:

1) increases

2) decreases

3) does not change

Decision.

The optical strength of the lenses is inversely proportional to its focal length, expressed in meters:. Since the focal length of the lens is invariably, its optical force is still unchanged.

It can be seen from the figure that when the object is removed from the lens (red line), its image decreases.

Answer: 32.

3. In the current model of the radio transmitter, the electrostilence of the capacitor, which is part of its oscillatory circuit, has changed, reducing the distance between its plates. How will the frequency of the fluctuations of the current in the circuit and the radiation wavelength change?

1) increase

2) will decrease

3) will not change

Decision.

The period of oscillations of the oscillating circuit is determined by the formula

and with a decrease in distance D, the capacitance capacitor increases. Then from the first formula it is clear that the period of oscillations T of the oscillating circuit will increase. Accordingly, the frequency of oscillations V \u003d 1 / T will decrease, and the wavelength - increase.

Answer: 21.

4. In the current model of the radio transmitter, the electrostility of the capacitor included in its oscillating circuit, increasing the distance between its plates. How will the frequency of current fluctuations in the circuit and the speed of electromagnetic radiation change?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

The oscillating circuit oscillations period is determined by the Thompson formula:

where L is the inductance of the coil; C - capacitance capacitor. The capacitance of the capacitor is associated with distance D between its plates by expression:

and with an increase in distance D capacitance of the capacitor decreases. Then from the first formula it is clear that the period of oscillations T of the oscillating circuit decreases. Accordingly, the oscillation frequency V \u003d 1 / T will increase, and the spreading rate of the electromagnetic radiation of the wave will not change, because When the frequency changes, the wavelength is changed and the speed is determined, and the speed is defined as.

Answer: 13.

5. α-particle moving in vacuum at speed V<< с, пролетает между пластинами заряжённого конденсатора так, как показано на рисунке. Пролетев конденсатор, частица отклоняется от первоначального направления на угол α.

How will the kinetic energy of the flowing particle and angle α change, if you increase the voltage between the condenser plates?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

Where E is the electric field strength; Q - particle charge. If the voltage between the plates of the charged condenser is to increase, then the intensity of the field E will increase, and the strength F will increase. Since the force F is directed perpendicular to the movement of the particle, then with an increase in the voltage, it will deviate from the initial (horizontal) direction to the larger angle, then There is an angle α will increase.

In the horizontal plane, the particle speed remains unchanged, and in the vertical plane it is given an additional acceleration, which deflects the particle to the angle α. Consequently, the particle speed module will increase, and therefore its kinetic energy will increase.

Answer: 11.

6. α-particle moving in vacuum at speed V<< с, пролетает между пластинами заряжённого конденсатора так, как показано на рисунке. Как изменится импульс вылетевшей частицы и время пролёта в конденсаторе, если уменьшить напряжение между пластинами конденсатора?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

The force on the part of the electric field is powerwhere E is the electric field strength; Q - particle charge. If the voltage between the plates of the charged condenser is reduced, then the field strength E decreases, and the strength F will decrease. Since the force F is directed perpendicular to the particle movement, then when the voltage decreases, it will deviate from the initial (horizontal) direction to the smaller angle, then There is an angle α decreases.

In the horizontal plane, the particle speed remains unchanged, it means that the time of the span of the particles through the capacitor will remain the same. In the vertical plane, it is given an additional acceleration, which deflects the particle to the angle α. Consequently, the particle speed module will decrease, which means it will decrease and its impulse equal to P \u003d MV.

Answer: 23.

7.Unspractified DC electrical circuit consists of a current source and an external resistor connected to its conclusions. How to change when the resistor resistance is reduced by the power of the current in the circuit and the EMF source?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

Current strength in the chain can be determined by the Ohm law for the full chain:

where E - EMF source; R is the internal resistance of the current source; R is the external chain resistance. From this formula it follows that with a decrease in R, the current in the chain will increase. EMF source The value is constant and does not depend on the external chain.

Answer: 13.

8. Unspractified DC electrical circuit consists of a current source and an external resistor connected to its conclusions. How to change with an increase in the resistance of the resistor internal resistance of the EMF source and voltage on the source terminals?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

The internal resistance of the source of the EMF depends only on the design of the source itself and is not associated with the external resistance of the chain, so it will not change.

The voltage on the source terminals determines the voltage drop on the outer chain according to the lawwhere R is the resistance of the outer chain, I is the current of the current in the chain. With an increase in R, the strength I remains the same, therefore, the voltage U on the source terminals will increase.

Answer: 31.

9. The α particle moves around the circumference in a homogeneous magnetic field between the magnet poles under the action of Lorentz's strength. After replacing the magnet, protons with the same speed began to move along the same trajectories. How changed the induction of the magnetic field and the Lorentz power module?

For each value, determine the corresponding nature of the change:

1) increased

2) decreased

3) has not changed

Decision.

where

and the power of Lorentz

.

(decrease by 2 times).

Answer: 22.

10. The α particle moves around the circumference in a homogeneous magnetic field between the magnet poles under the action of Lorentz's strength. After replacing the magnet, the protons with the same kinetic energy began to move along the same trajectories. How changed the induction of the magnetic field and the Lorentz power module?

For each value, determine the corresponding nature of the change:

1) increased

2) decreased

3) has not changed

Decision.

The Lorentz power acts on the α-particle from the magnetic fieldwhere q is a particle charge; V - particle speed; B - magnetic field strength. Since the α particle moves around the circumference, the magnetic field is directed perpendicular to its movement, that is, And the power of Lorentz in this case will be recorded in the form

In accordance with the Second Law of Newton, Lorentz's strength can also be written as

where - Centripetal acceleration. We obtain the value of the induction of the magnetic field strength:

and the power of Lorentz

.

Alpha particle has in its composition two protons and two neutrons, that is, its mass is 4 times the mass of the proton, and the charge is 2 times the batter of the proton.

Consequently, Lorentz's power in the case of protons will become equal:

(decrease by 4 times), and the induction of the magnetic field:

(decrease by 2 times).

Quest answer: 33.

11. The flat condenser was charged and disconnected from the galvanic element. How will change when a reduction in the gap between the capacitor plates capacitor capacitance and the charge value on its plates?

1) increase

2) will decrease

3) will not change

Decision.

Capacity C capacitor depends on distance d between its plates by the formula

where - absolute dielectric permeability of the environment between the plates; S - Planmark area. From this formula, it can be seen that with a decrease in D, the capacitance of the capacitor increases.

The charge on the capacitor plays will remain the same, as it has been disconnected from the current source.

Answer: 13.

12. A flat air capacitor with a dielectric between the plates is connected to the battery. Do not shut down the capacitor from the battery, the dielectric was removed from the condenser. How do the capacitance capacitance and the potential difference between its plates change?

1) increase

2) will decrease

3) will not change

Decision.

The container depending on the dielectric is determined by the expression

where - relative dielectric constant; - absolute dielectric constant; S - the area of \u200b\u200bthe condenser plates; D - distance between the plates. From this formula, it can be seen that when the dielectric is removed, the value Decrease, therefore, the capacitor capacity will decrease.

Since the capacitor is not disconnected from the battery, the potential difference between it does not change.

Answer: 23.

13. In a transparent vessel filled with water, a diffraction grid is located. The lattice is illuminated by the beam of light laser pointer, falling perpendicular to its surface through the side wall of the vessel. How will the frequency of the light wave falling on the grille and the angle between the normal to the lattice and the direction on the first diffraction maximum when removing water from the vessel?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

where V is the speed of propagation of waves; U is the frequency of oscillations. Moreover, the higher the refraction, the less the wavelength. That is, when removing water from the vessel, the wavelength will increase.

Ray deflection angle (refractive angle). Since the length of the wave increases, and the values \u200b\u200bof D, K remain unchanged, then the angle

will become more.

Answer: 31.

14. In a transparent vessel filled with water, a diffraction grid is located. The grille is illuminated by a parallel bunch of monochromatic light, falling perpendicular to its surface through the side wall of the vessel. How will the length of the light wave falling on the grid change, and the angle between the normal to the lattice and the direction on the first diffraction maximum when replacing water in the vessel with a transparent liquid with a large refractive index?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

The frequency of light will remain unchanged when moving from one medium to another, its length and speed changes. The wavelength is associated with the speed and frequency of fluctuations in the expression

where V is the speed of propagation of waves; U is the frequency of oscillations. It is known that the more denser the medium, the lower the speed of the wave propagation. That is, when replacing water to liquid with a large refractive index, the wavelength will decrease.

The angle of deflection of the rays and the first diffraction maximum is connected by the expression

where k is the order of the spectrum (in this case k \u003d 1); λ - wavelength; d - constant diffraction lattice (depends on the number of bands per unit length); - The angle of deflection of the rays (the corner of the refraction). Since the wavelength decreases, and the values \u200b\u200bD, K remain unchanged, then the angle

will become less.

Answer: 22.

15. The unbranched electrical circuit consists of a source of constant voltage and resistor. How to change with an increase in the internal resistance of the source the power of the current in the chain and voltage on the resistor? For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

Ohm's Law for Complete Chain is

where R is the external resistance of the chain; R is the internal resistance of the source; I - the power of the current in the chain; E - EDS source. It follows that the current is equal to

If the internal resistance R increases, the current strength I decreases. With a decrease in the current force, in accordance with the law of Ohm, resistance voltage Also decrease.

Answer: 22.

16. The unbranched electrical circuit consists of a source of constant voltage and resistor. How will change with a decrease in the internal resistance of the source power released on the resistor and the electromotive power of the source?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

EMF of the current source does not depend on internal resistance. In this case, out of the law of Oma for the full chain, it can be concluded that the current of the current in the chain will increase and will be equal to

where R is the internal resistance of the current source; R is the external chain resistance.

Since the current in the chain becomes more, then the power allocated on the resistor, Also increase.

Answer: 13.

17. When adjusting the oscillatory loop of the radio transmitter, its inductance has decreased. How will the frequency of the emitted waves change and the radiation wavelength change?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

The frequency of radiated waves is proportional to the frequency of oscillations in the oscillatory circuit. The frequency of oscillations in the circuit is determined by the formulawhere it can be seen that with a decrease in the inductance L, the frequency increases.

Radiation wavelength equal And with increasing frequency V, the wavelength decreases.

Answer: 12.

18. When setting the oscillatory loop of the radio transmitter, its inductance increased. How will the period of current fluctuations in the circuit and the wavelength of the electromagnetic radiation change?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

The period of oscillations in the oscillatory circuit is determined by the expression

and with an increase in the inductance of the coil L, the period of oscillations increases.

The frequency of oscillations in the circuit is determined by the formula, and with increasing T, it decreases. Radiation wavelength equal And with a decrease in the frequency V, the wavelength increases.

Answer: 11.

19. Over wire resistor flows current. How to change with a decrease in wire length 4 times and increasing the current strength by half the thermal power released on the resistor and its electrical resistance?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

Where - Length of the wire; S is a cross-section of the wire. If the wire length is reduced 4 times, then the resistance will become equal

,

that is, it will decrease by 4 times. Then the power released on the resistance with increasing current increases by 2 times will be equal to

,

that is, it will not change.

Answer: 32.

20. Over wire resistor flows current. How to change with a decrease in wire length 2 times and increasing the current strength by half the thermal power released on the resistor and its electrical resistance?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

Thermal power released on the resistance is proportional to the current power. In turn, resistancewhere - Specific resistivity; - Length of the wire; S is a cross-section of the wire. If the wire length is reduced by 2 times, then the resistance will become equal

,

that is, it will decrease by 2 times. Then the power released on the resistance with increasing current increases by 2 times will be equal to

,

that is, it will increase by 2 times.

Answer: 12.

21. In the diagram shown in Figure, R1\u003e R2. What happens to the ammeter and voltmeter readings after switching the key to position 1 to position 2? For each value, determine the corresponding nature of its change:

1) increase

2) will decrease

3) will not change

Decision.

The ammeter shows the current in the chain. The value of the current is determined from the Ohm law for the full chain by the formula

.

Since the EMF of the source E and its inner resistance R is constant, then when choosing a resistor R2 with less resistance, the current in the chain will increase.

The testimony of the voltmeter can be found from the law of Oma U \u003d IR or in the form of

.

It can be seen that with a decrease in resistance R voltage U decreases.

Answer: 12.

. In the diagram shown in Figure, R1< R2. Что произойдёт с показаниями амперметра и вольтметра после переключения ключа К из положения 1 в положение 2? Для каждой величины определите соответствующий характер её изменения:

1) increase

2) will decrease

3) will not change

Decision.

The ammeter shows the current in the chain. In this case, the current value is determined from the Ohm law for the full chain by the formula

.

This formula shows that when choosing a resistor R2 with a large resistance and at a constant EMF of the source E and its internal resistance R, then the current in the chain decreases.

Voltmeter readings can be found from the law of OM U \u003d IR, which can be written as

.

It can be seen that with increasing resistance R voltage U increases.

Answer: 21.

23. The student conducted experience in the refraction of the light, presented in the figure. How to change when a decrease in the angle of incidence of the refractive area spreading in glass and the refractive index of glass?

1) increase

2) will decrease

3) will not change

Decision.

,

where n is the refractive index of glass. Since the refractive index in the experiment does not change (it depends on the glass material, that is, from its optical properties), then with a decrease in the angle of the fall α, the refractive angle γ is also reduced (since, with a decrease in the angle of the sine of this angle, it is also reduced).

Answer: 23.

24. The student conducted experience in the refraction of the light, presented in the figure. How to change when angle increasing the angle of refraction of the light spreading in glass and the refractive index of glass?

1) increase

2) will decrease

3) will not change

Decision.

Sinus angle of the incidence of α and sinus of the refractive index γ are interconnected by expression

,

where n is the refractive index of glass. Since the refractive index in the experiment does not change (it depends on the glass material, that is, from its optical properties), then with increasing the angle of the fall α, the refractive angle γ will also increase (since, with an increase in the angle, the sinus of this angle is also increasing).

Answer: 13.

25. When adjusting the oscillatory loop of the radio transmitter, its inductance has decreased. How did the current fluctuations in the circuit and the radiation wavelength changed?

For each value, determine the corresponding nature of the change:

1) increased

2) decreased

3) has not changed

Decision.

The period of oscillations of the current in the oscillatory circuit is determined by the expression and with a decrease in the inductance L period will also decrease. The length of the radiation wave is associated with the period of oscillations by expression

,

where C is the speed of the wave; V \u003d 1 / T - the frequency of the wave. From this formula, it can be seen that with a decrease in the period of oscillations, the wavelength decreases.

Answer: 22.

26. When adjusting the oscillatory loop of the radio transmitter, the capacitance of the capacitor incoming in it increased. How did the current oscillation frequency in the circuit and the radiation wavelength changed?

For each value, determine the corresponding nature of the change:

1) increased

2) decreased

3) has not changed

Decision.

The frequency of oscillations of the contour is determined by the formula

and with an increase in the capacitance C frequency decreases. The radiation wavelength is associated with the frequency of oscillations of the oscillatory contour by expression:

,

where C is the speed of radio wave. From this formula, it can be seen that with a decrease in frequency, the wavelength increases.

Answer: 21.

27. The proton in a homogeneous magnetic field is moving around the circle. How will the radius of the circle and the transaction period change, if its speed increase?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

,

and the power of Lorentz is equal

.

from where the radius of the orbit is equal to:

. (1)

From this formula, it can be seen that with increasing speed, the radius of the proton orbit increases.

. From formula (1) it can be seen that with increasing speed, the radius of the circle increases at the same time, consequently, the period of treatment is equal to

,

will remain the same.

Answer: 13.

28. The proton in a homogeneous magnetic field is moving around the circle. How will the radius of the circle and the transaction period change, if its speed decreases?

For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

From the magnetic field, the Lorentz power acts on the proton, equal

,

and since the proton is moving around the circumference, then the angle and the power of Lorentz is equal

.

In accordance with the second law of Newton F \u003d MA, where - Centripetal acceleration of the proton, we get:

from where the radius of the orbit is equal to:

. (1)

From this formula, it is clear that with a decrease in the speed, the radius of the proton orbit decreases.

The proton circulation period is the time for which it makes one full turn, that is, the time for which he passes the distance equal . From formula (1) it can be seen that with a decrease in speed, the radius of the circle decreases to the same time, therefore, the period of treatment is equal to

,

will remain the same.

Answer: 23.

29. The figure shows a DC circuit containing a current source with EDC E and two resistors: R1 and R2. If the key to close, then how the current is changed through the resistor and the total thermal power released at the external section of the chain? Internal resistance of the current source neglected.

1) increase

2) will decrease

3) will not change

Decision.

.

Before closing the key, the external chain resistance is equal and the current is equal

. (1)

After closing the key, the current began to flow only through the resistor R1 and the external resistance of the chain was equal to R \u003d R1, therefore, we have a current

. (2)

From formulas (1) and (2) it can be seen that when closing the key, the current in the chain increases.

The power released on the external circuit is equal to

Before the key closure power

, (3)

and after closing the key

. (4)

From formulas (3) and (4) it can be seen that the power released after the closure of the key is more power up to the closure, that is, it increases.

30. The figure shows a DC circuit containing a current source with EDC E and two resistors R1 and R2. Initially the key is closed. If the key to break, then how will the overall resistance of the external section of the chain and voltage on the R1 resistor change? Internal resistance of the current source neglected. For each value, determine the corresponding nature of the change:

1) increase

2) will decrease

3) will not change

Decision.

In accordance with the Ohm law for the full chain, the current in the circuit is equal to

and at zero internal resistance R \u003d 0, we get:

.

With a closed key, the external resistance of the chain is equal and the current is equal

.

In accordance with the law of OBA, the stress on resistance R1 is equal

. (1)

After opening the key, the current began to flow through resistors R1 and R2 and the external resistance of the chain was equal to , therefore, the current in the chain became equal

and voltage at resistance R1:

. (2)

From formulas (1) and (2) it can be seen that when the key is blurred, the chain resistance increases, and the voltage at the resistance R1 decreases.

Answer: 12.

Topics: electricity , sequential and parallel conductor compound, diffraction grille, refraction of light, electromagnetic oscillations, option 1 Task 17. Over a wire resistor flows current. The resistor was replaced on another, with a wire from the same metal and the same length, but having a smaller cross-sectional area, and they missed a smaller current through it. How do the voltage on the resistor and its resistance change? For each value, determine the appropriate nature of the change: 1) 2) will increase 3) Option 2 will not change. Task 17. The current flow flows. The resistor was replaced on another, with a wire from the same metal and the same cross section, but twice as smaller length, and they missed the smaller current through it. How do the voltage on the resistor and its resistance change? For each value, determine the appropriate nature of the change: 1) 2) will decrease 3) The option 3 tasks 17. A flat condenser with an air gap between the plates is connected to a constant voltage source. How will change when a reduction in the gap between the capacitor plays is electrostatura and the charge value on its plates? For each value, determine the appropriate nature of the change: 1) 2) will decrease 3) the option 4 task 17. A flat condenser with an air gap between the plates is connected to a constant voltage source. How will the field intensity change in the gap between the condenser's plates and the charge value on its plates, if you increase the gap between them? For each value, determine the appropriate character of the change: 1) 2) will decrease 3) Embodiment 5 The task 17 will not change. The charged particle mass M, moving at a speed V, flies in a field of a flat capacitor (see Figure). The distance between the capacitor plates is d, and the voltage of the electric field between the plates is equal to E. The condenser is flying, the particle deviates from the initial direction to the angle a. How will the velocity module change the particle and angle A, if you reduce the magnitude of the electric fields between the condenser plates? For each value, determine the appropriate nature of the change: 1) 2) will increase 3) Embodiment 6 Task 17. The charged particle mass M, moving at a speed V, flies in a field of a flat capacitor (see Figure). The distance between the plates of the capacitor is d, the length of the plates L \u003e\u003e D, and the magnitude of the voltage of the electric field between the plates is equal to E. Flying the capacitor, the particle deviates from the initial direction to the angle a. How will the velocity module change the particle and angle A, if you increase the particle speed at the inlet to the condenser? 1) 2) will decrease 3) Embodiment 7 Task 17. The figure shows the DC circuit containing the current source with the EMF resistor R1 and R2 Resistor. If you reduce the resistance of R2 resistance to a minimum, then how the current is changed in the chain and the total thermal power released at the external section of the chain? Internal resistance of the current source neglected. For each value, determine the corresponding character of the change: 1) 2) will decrease 3) Embodiment 8 The task 17 will not change. The figure shows a DC circuit containing a current source with EDC E and two resistors: R1 and R2. If the key to closes, then how the current is changed through the R1 resistor and the voltage on the R2 resistor? Internal resistance of the current source neglected. For each value, determine the appropriate nature of the change: 1) 2) will increase 3) The option 9 task 17. The proton in a homogeneous magnetic field is moving around the circle. So that in this field moves around the circumference with the same velocity of the accenta, the circle radius and the accept rate frequency compared to the proton should: 1) increase 2) decrease 3) not to change the option 10 task 17. Proton in a homogeneous magnetic field moves around the circle. So that in this field moves around the circumference with the same velocity of the acceptic, the centripetal acceleration of the acoustic and the period of its appeal compared to the proton should: 1) increase 2) decrease 3) not to change the option 11 task 17. Flat air capacitor with a dielectric between the plates is connected to Battery. Do not shut down the capacitor from the battery, the dielectric was removed from the condenser. How do the capacitance capacitance and the potential difference between its plates change? 1) 2) 3) will decrease 3) Themes will not change: electric current, sequential and parallel conductor compound, diffraction grating, refraction of light, electromagnetic oscillations, option 12 Task 17. Flat air capacitor with a dielectric between the plates is connected to the battery. Do not shut down the capacitor from the battery, the dielectric was removed from the condenser. How do the capacitance capacitance and the potential difference between its plates change? 1) 2) will decrease 3) the option 13 task 17 will not change. In a transparent vessel filled with water, a diffraction grid is located. The lattice is illuminated by the beam of light laser pointer, falling perpendicular to its surface through the side wall of the vessel. How will the frequency of the light wave falling on the grille and the angle between the normal to the lattice and the direction on the first diffraction maximum when removing water from the vessel? For each value, determine the corresponding character of the change: 1) will increase 2) 3) will not change the option 14 task 17. In the transparent vessel filled with water, there is a diffraction grid. The grille is illuminated by a parallel bunch of monochromatic light, falling perpendicular to its surface through the side wall of the vessel. How will the length of the light wave falling on the grid change, and the angle between the normal to the lattice and the direction on the first diffraction maximum when replacing water in the vessel with a transparent liquid with a large refractive index? For each value, determine the corresponding nature of the change: 1) 2) will increase 3) Embodiment 15 Task 17. The unbreakable electrical circuit consists of a constant voltage source and a resistor. How to change with an increase in the internal resistance of the source the power of the current in the chain and voltage on the resistor? For each value, determine the corresponding character of the change: 1) 2) will increase 3) Embodiment 16 Task 17. The unbreakable electrical circuit consists of a constant voltage source and a resistor. How will change with a decrease in the internal resistance of the source power released on the resistor and the electromotive power of the source? For each value, determine the appropriate character of the change: 1) 2) will decrease 3) The option 17 task 17 will not change. When setting the oscillatory circuit of the radio transmitter, its inductance has decreased. How will the frequency of the emitted waves change and the radiation wavelength change? For each value, determine the appropriate nature of the change: 1) will increase 2) decrease 3) Embodiment will not change the option 18. When adjusting the oscillatory loaf of the radio transmitter, its inductance increased. How will the period of current fluctuations in the circuit and the wavelength of the electromagnetic radiation change? For each value, determine the corresponding character of the change: 1) 2) will increase 3) The option 19 task 17 will not change. The wire resistor flows current. How to change with a decrease in wire length 4 times and increasing the current strength by half the thermal power released on the resistor and its electrical resistance? For each value, determine the appropriate nature of the change: 1) will increase 2) it will decrease 3) The option 20 tasks 17. The current flows the current to the wire resistor. How to change with a decrease in wire length 2 times and increasing the current strength by half the thermal power released on the resistor and its electrical resistance? For each value, determine the corresponding character of the change: 1) 2) will increase 3) Embodiment 21 Task 17. In the diagram shown in Figure, R1\u003e R2. What happens to the ammeter and voltmeter readings after switching the key to position 1 to position 2? For each value, determine the corresponding character of its change: 1) increase 2) decrease 3) Embodiment 22 Task 17. In the diagram shown in Figure, R1< R2. Что произойдёт с показаниями амперметра и вольтметра после переключения ключа К из положения 1 в положение 2? Для каждой величины определите соответствующий характер её изменения: 1) увеличится 2) уменьшится 3) не изменится Темы: электрический ток, последовательное и параллельное соединение проводников, дифракционная решетка, преломление света, электромагнитные колебания, Вариант 23 Задание 17. Ученик провёл опыт по преломлению света, представленный на рисунке. Как изменятся при уменьшении угла падения угол преломления света, распространяющегося в стекле, и показатель преломления стекла? 1) увеличится 2) уменьшится 3) не изменится Вариант 24 Задание 17. Ученик провёл опыт по преломлению света, представленный на рисунке. Как изменятся при увеличении угла падения угол преломления света, распространяющегося в стекле, и показатель преломления стекла? 1) увеличится 2) уменьшится 3) не изменится Вариант 25 Задание 17. При настройке колебательного контура радиопередатчика его индуктивность уменьшили. Как при этом изменились период колебаний тока в контуре и длины волны излучения? Для каждой величины определите соответствующий характер изменения: 1) увеличилась 2) уменьшилась 3) не изменилась Вариант 26 Задание 17. При настройке колебательного контура радиопередатчика ёмкость входящего в него конденсатора увеличили. Как при этом изменились частота колебаний тока в контуре и длина волны излучения? Для каждой величины определите соответствующий характер изменения: 1) увеличилась 2) уменьшилась 3) не изменилась Вариант 28 Задание 17. Протон в однородном магнитном поле движется по окружности. Как изменятся радиус окружности и период обращения протона, если его скорость уменьшится? Для каждой величины определите соответствующий характер изменения: 1) увеличится 2) уменьшится 3) не изменится Вариант 29 Задание 17. На рисунке показана цепь постоянного тока, содержащая источник тока с ЭДС E и два резистора: R1 и R2. Если ключ К замкнуть, то как изменятся сила тока через резистор и суммарная тепловая мощность, выделяющаяся на внешнем участке цепи? Внутренним сопротивлением источника тока пренебречь. 1) увеличится 2) уменьшится 3) не изменится Вариант 30 Задание 17. На рисунке показана цепь постоянного тока, содержащая источник тока с ЭДС E и два резистора R1 и R2. Первоначально ключ К замкнут. Если ключ К разомкнуть, то как изменятся общее сопротивление внешнего участка цепи и напряжение на резисторе R1? Внутренним сопротивлением источника тока пренебречь. Для каждой величины определите соответствующий характер изменения: 1) увеличится 2) уменьшится 3) не изменится