AP Physics Physics: Electricity & Magnetism 2

Question 1

A parallel-plate capacitor is fully charged and then disconnected from the battery. If the plate separation is doubled, what happens to the voltage across the capacitor?

Accepted Answer

It doubles

Answer

It halves

Answer

It stays the same

Answer

It quadruples

Question 2

Two long parallel wires carry currents in the same direction. The magnetic force between them is:

Accepted Answer

Attractive

Answer

Repulsive

Answer

Zero

Answer

Dependent only on their resistance

Question 3

A proton moves horizontally to the right through a uniform magnetic field directed into the page. The magnetic force on the proton is directed:

Accepted Answer

Upward

Answer

Into the page

Answer

Out of the page

Answer

Downward

Question 4

Which of the following correctly describes the electric field inside a conductor in electrostatic equilibrium?

Accepted Answer

It is zero

Answer

It equals the surface charge density divided by ε₀

Answer

It points radially outward from the center

Answer

It equals the external applied field

Question 5

A solenoid with N turns, length L, and cross-sectional area A carries current I. Its self-inductance is:

Accepted Answer

μ₀N²A/L

Answer

μ₀NA/L

Answer

μ₀NI/L

Answer

μ₀N²I/L

Question 6

Three resistors of 2 Ω, 4 Ω, and 6 Ω are connected in parallel. What is the equivalent resistance?

Accepted Answer

1.09 Ω

Answer

12 Ω

Answer

4 Ω

Answer

0.92 Ω

Question 7

Gauss's Law states that the net electric flux through any closed surface equals:

Accepted Answer

The total charge enclosed divided by ε₀

Answer

The product of electric field and surface area

Answer

The surface charge density times the area

Answer

Zero for any closed surface