?

AP® Physics C: E & M

Free Version

Upgrade subject to access all content

Easy

Conducting Spheres Contact: Different Radii, Electron Flow

APPHEM-RWGHB1

A conducting sphere with radius 4.0 cm has a net positive charge on it. The sphere is then connected with a metal wire to a second, uncharged, sphere of radius 1.0 cm.

Which statement below BEST describes the flow of electrons when the metal wire connects the two spheres?

A

Electrons flow from the 4.0-cm radius sphere to the 1.0-cm radius sphere, leaving the 4.0-cm radius sphere with a net charge of zero.

B

Electrons flow from the 1.0-cm radius sphere to the 4.0-cm radius sphere, until both spheres have the same net positive charge.

C

Electrons flow from the 4.0-cm radius sphere to the 1.0-cm radius sphere until both spheres have the same net positive charge.

D

Electrons flow from the 1.0-cm radius sphere to the 4.0-cm radius sphere until the surfaces of both spheres are at the same electric potential.

E

Electrons do not flow along the wire, because the system is already in equilibrium.