Question

Electrons are emitted from a conductor when the conductor is

A. bombarded by high-speed electrons.
B. subjected to a small voltage.
C. cooled rapidly.
D. exposed to weak light.

Answer 1

Well, I have personally used both A and C (provided the light frequency takes it above the work function of the condutor).

D could also work - a good conductor subject to a small voltage will carry a very large current. For instance, a flashlightg bulb filament is hot enough to emit electrons.

B is a no go.