PH 112 Final Review

A suspended Object A is attracted to a neutral wall. It's also attracted to a negatively charged object B. Object A is therefore...

Uncharged

Negatively Charged

Positively Charged

Could be positively or negatively charged

Positively Charged

Which of the following best explains the key difference between conductors and insulators?

Conductors allow heat to move freely, while insulators do not

Conductors allow electric charge to move freely, while insulators do not

Conductors have high density, while insulators have low density.

Conductors are typically metals, while insulators are non-metals

Conductors allow electric charge to move freely, while insulators do not

Object A has a charge of +9 nC, and Object B has a charge of +1 nC. The force between the charges is...

Attractive

Repulsive

Neither Attractive nor Repulsive

Cannot be Determined

Repulsive

Object A has a charge of +9 nC, and Object B has a charge of +1 nC. The magnitude force on Object A is _____ on Object B.

9x stronger than

81x stronger than

9x weaker than

81x weaker than

equal to that

equal to that

Two objects initially experience an electrical force F. If the distance between the two objects is halved, by what factor does the force change?

1/4

1/2

2

4

4

In which region would you expect to find a point where the electric field is zero?

Region I

Region II

Region III

Region III

A negative charge is placed in an electric field. The force on this negative charge is _______ to the electric field.

perpendicular

a parallel

anti-parallel

out of phase

anti-parallel

A negative test charge is put in an external electric field. The negative test charge is then replaced with positive test charge of equal magnitude.

It has the same magnitude but changes direction

It increases in magnitude and changes direction.

It decreases in magnitude and changes direction

It remains the same.

It remains the same.

A free electron and a free proton are placed one-at-a-time in an external electric field. The particles experience the same acceleration.

True

False

False

A free electron and a free proton are placed one-at-a-time in an external electric field. The particles experience the same force.

True

False

True

What is the electric flux through the closed surface in the image?

-1 µC/eps0

0

+1 µC/eps0

+1 µC/eps0

Consider an arbitrary closed surface. Charges outside the surface affect the net flux through the surface.

True

False

False

If a proton is released from rest in a uniform electric field, the proton would begin moving such that the electric potential energy...

Increases

Decreases

Remains the same

Decreases

If an electron is released from rest in a uniform electric field, the electron would move toward electric potential.

Higher

Lower

an equipotential

Higher

Electric potential can increase while potential energy decreases.

True

False

True

An electron is placed at Point A and given a small kick to the right. What will its subsequent motion be?

it will go to the right and not return

It will go to the left

It will remain at Point A

It will oscillate about Point A

It will oscillate about Point A

An object can be accelerated (experience a force) when V = 0.

True

False

True

A spherical balloon contains a positively charged particle at its center. As the balloon is inflated, which of the following statements is true?

The electric potential at the surface of the balloon increases.

The magnitude of the electric field at the surface of the balloon increases.

The electric flux through the balloon remains the same.

None of these.

The electric flux through the balloon remains the same

An electron and a proton are accelerated through a potential difference of 1 V magnitude. Which has the higher KE after this?

The Proton

The Electron

They have the same KE

Cannot be determined.

They have the same KE

An electron and a proton are accelerated through a potential difference of 1 V magnitude. Which has the higher velocity after this?

The Proton

The Electron

They have the same KE

Cannot be determined.

The Electron

A sphere has a capacitance of 1 µF and carries a charge of 20 µC. If the charge is increased to 60 µC, what is the sphere's new capacitance?

Less than 1 µF

Equal to 1 µF

Greater than 1 µF

Not enough information.

Equal to 1 µF

How is the capacitance affected if the potential across a cylindrical capacitor is increased from 20 V to 80 V?

It increases

It decreases.

It remains the same

It remains the same

How is the stored charge affected if the potential across a cylindrical capacitor is increased from 20 V to 80 V?

It increases

It decreases.

It remains the same

It increases

For capacitors connected in parallel, the equivalent capacitance will always be

Greater than the highest individual capacitance

Equal to the median capacitance

Lesser than the lowest individual capacitance

Greater than the highest individual capacitance

For capacitors connected in series, the equivalent capacitance will always be

Greater than the highest individual capacitance

Equal to the median capacitance

Lesser than the lowest individual capacitance

Lesser than the lowest individual capacitance

The current carried by wire A is twice the current carried by the identical wire B. In which wire do the charge carriers have the higher drift speed?

Wire A

Wire B

Wire C

They have the some drift speed

Wire A

Suppose a current-carrying wire has a cross-sectional area that gradually becomes larger along the wire. How does the drift speed vary along the wire?

It slows down as the cross section becomes larger

It speeds up as the cross section becomes smaller.

It doesn't change

Cannot be determined.

It slows down as the cross section becomes larger

If the radius and the length of a wire are reduced to half their original size, the resistance should then.

Increase

Decrease

Remain the same

Increase

Two resistors, A and B, are connected in parallel with a battery and to each other. Resistor B has twice the resistance as A. Which resistor dissipates the most amount of power?

Resistor A

Resistor B

They dissipate the same power

Resistor A

The terminal voltage of a battery is always greater than or equal to the emf of the battery.

True

False

False

For which case(s) do you expect the discharging time of an RC Circuit to increase for a given system.

Increase resistance

Increase capacitance

Decrease resistance

Decrease capacitance.

Increase resistance

Increase capacitance

For a discharging RC circuit, we expect both charge on the capacitor and system current to decrease over time.

True

False

True

For a charging RC circuit, we expect both charge on the capacitor and system current to increase over time.

False

A charged particle is moving in a straight line through a magnetic field. You therefore expect the particle's velocity and the magnetic field to be.....

Parallel

Perpendicular

Parallel or Perpendicular

Between parallel and perpendicular

Not magnetic fields again

Parallel

Since the magnetic force is always perpendicular to the particle's velocity, magnetic forces do ___ work on particles.

Positive

Negative

No

No

Magnetic fields tend to _____ the KE of charged particles moving through them.

increase

decrease

do not change

do not change

In what direction is the magnetic force on the moving positively charged particle?

Toward the Top of the Screen

Toward the Bottom of the Screen

To the Left

To the Right

Into the Screen

Out of the Screen

Into the Screen

In what direction is the magnetic force on the moving positively charged particle?

Toward the Top of the Screen

Toward the Bottom of the Screen

To the Left

To the Right

Into the Screen

Out of the Screen

Toward the Top of the Screen

A current-carrying loop is placed in a uniform magnetic field. How does the magnetic torque on the loop behave?

The torque is zero if the magnetic field is parallel to the plane of the loop.

The torque is maximum when the magnetic field is parallel to the loop's magnetic moment.

The torque seeks to align the plane of the loop to be perpendicular to the magnetic field.

The torque does not depend on the orientation of the loop relative to the field

The torque seeks to align the plane of the loop to be perpendicular to the magnetic field.

In the Hall effect, what is the primary reason a potential difference is developed across the conductor?

The magnetic field induces an electric field across the conductor

The charge carriers experience a force perpendicular to both the magnetic field and current

The current increases in the presence of the magnetic field.

The conductor's resistance decreases due to the magnetic field

The charge carriers experience a force perpendicular to both the magnetic field and current

A point charge is moving with a constant velocity. What best describes the magnetic field it generates?

The magnetic field is strongest along the direction of motion of the charge

The magnetic field is circular around the path of the moving charge

The magnetic field is uniform and does not depend on the speed of the charge

The magnetic field exists only if the charge is accelerating

The magnetic field is circular around the path of the moving charge

Which of the following best describes the magnetic field inside a long, current-carrying solenoid?

The interior magnetic field is non-uniform and decreases along the length of the solenoid

The interior magnetic field is uniform and directed parallel to the axis of the solenoid

The magnetic field is strongest outside the solenoid and weaker inside

The interior magnetic field is uniform and directed parallel to the axis of the solenoid

The two wires shown carry equal and opposite currents. At the midpoint between the currents, the magnetic field is...

Zero

Into the Screen

Out of the Screen

Toward the Top of the Screen

Toward the Bottom of the Screen

Out of the Screen

If instead, the currents were in the same direction: At the midpoint between the currents, the magnetic field is...

Zero

Into the Screen

Out of the Screen

Toward the Top of the Screen

Toward the Bottom of the Screen

Zero

Two parallel wires carry current in the same direction. Wire 1 has current I while wire 2 double the current. Which wire experiences greater force?

Wire 1

Wire 2

They experience the same magnitude force.

They experience the same magnitude force.

When a current is passed through the wire in the figure, will the wire tend to bunch up or will it tend to form a circle?

Bunch Up

Form a Circle

Not enough information

Form a Circle

Which of the following statements is true about the application of Ampere's Law?

Ampere’s Law can only be applied if the current distribution is uniform

Ampere's Law applies only to circular paths

Amperes Law cannot be used when there is no current enclosed

None of these

None of these

In which direction is the induced emf/current?

Clockwise

Counter-Clockwise

No Induced Current

Clockwise

In which direction is the induced emf/current?

Clockwise

Counter-Clockwise

No Induced Current

Clockwise

In which direction is the induced emf/current?

Clockwise

Counter-Clockwise

No Induced Current

No Induced Current

Two objects with different sizes, masses, and temperatures are placed in thermal contact. Energy travels

from the larger to the smaller

from the more massive to less massive

from the higher temperature object to lower temperature

It depends on the combination of their relative sizes, masses, and temperatures

from the higher temperature object to lower temperature

When the temperature of an ideal gas in a sealed container is increased, which of the following will happen if the volume is held constant?

The pressure will decrease

The pressure will remain constant

The pressure will increase

The number of gas molecules will decrease

The pressure will increase

If the volume of an ideal gas is doubled while the temperature and amount of gas remain constant. what happens to the pressure?

It doubles

It remains the same

It is halved

It increases by a factor of four

It is halved

Which of the following changes would increase the volume of an ideal gas in a flexible container, assuming constant pressure?

Increasing the number of moles of gas

Decreasing the temperature

Decreasing the number of moles of gas

Increasing the temperature

Increasing the number of moles of gas

Increasing the temperature

Water (highest specific heat), iron, and lead (lowest specific heat) of equal masses are all at 10 Celsius. Which has the greatest heat?

Water

Iron

Lead

Objects do not contain heat.

Objects do not contain heat.

When a solid turns into a liquid at its melting point, which of the following happens to the temperature?

It decreases as the solid absorbs heat

It stays constant until all the solid has melted.

It increases steadily during melting

It stays constant but only if additional heat isn't added

It stays constant until all the solid has melted.

The pressure of a gas must remain constant for work to be done on the gas.

True

False

False

The volume of a gas must change as work is done on/by the gas.

True

False

True

In an isothermal process for an ideal gas, how does the work done by the gas relate to the heat added to the system?

The work done is greater than the heat added

The work done is equal to the heat added

The work done is less than the heat added

No work is done during an isothermal process

The work done is equal to the heat added

During an isobaric expansion of an ideal gas, which describes the work done by the gas?

It is proportional to the change in temperature

It is proportional to the change in pressure.

It is proportional to the change in volume

It is zero because the pressure is constant

It is proportional to the change in volume

For an adiabatic expansion of an ideal gas, what happens to the internal energy of the gas?

It increases because no heat is exchanged

It decreases because the gas does work on its surroundings.

It remains constant because no heat is exchanged.

It depends on the specific heat capacity of the gas

It decreases because the gas does work on its surroundings.

According to the graph attached, Process A is...

Adiabatic

Isochoric

Isobaric

Isothermal

Isochoric

According to the graph attached, Process B is...

Adiabatic

Isochoric

Isobaric

Isothermal

Adiabatic

According to the graph attached, Process C is...

Adiabatic

Isochoric

Isobaric

Isothermal

Isothermal

According to the graph attached, Process D is...

Adiabatic

Isochoric

Isobaric

Isothermal

Isobaric