Question
Physics Question on Photoelectric Effect
The collector plate in an experiment on photoelectric effect is kept vertically above the emitter plate. Light source is put on and a saturation photo-current is recorded. An electric field is switched on which has a vertically downward direction, then
A
the photo-current will increase
B
the kinetic energy of the electrons will increase
C
the stopping potential will decrease
D
the threshold wavelength will increase
Answer
the kinetic energy of the electrons will increase
Explanation
Solution
In electric field photoelectron will experience force and accelerate opposite to the field so its KE increases (ie, stopping potential will increase), no change in photoelectric current, and threshold wavelength.