Discussion Forum



1)

If the wavelength is brought down from  6000Å  to 4000Å in a photoelectric experiment then what will happen?


A) The work function of the metal will increase

B) The threshold frequency will decrease

C) No change will take place

D) Cut off voltage will increase

Answer:

Option D

Explanation:

When wavelength decreases, frequency increase, Also we know that cut off voltage (or stopping potential)  increases when frequency increases.

 Hence, option (d)  is correct. Note that work function and threshold frequency are constant for a given metal.