### Neet Solved Paper 2013 Question 37

##### Question: For photoelectric emission from certain metal the cut-off frequency is v. If radiation of frequency 2v impinges on the metal plate, the maximum possible velocity of the emitted electron will be (m is the electron mass)

#### Options:

A) $ \sqrt{\frac{hv}{(2m)}} $

B) $ \sqrt{\frac{hv}{m}} $

C) $ \sqrt{\frac{2hv}{m}} $

D) $ \sqrt[2]{\frac{hv}{m}} $

## Show Answer

#### Answer:

Correct Answer: C

#### Solution:

As $ \frac{1}{2}mv _{\max }^{2}=hv $

$ \Rightarrow $ $ v _{\max }^{2}=\frac{2hv}{m} $

$ \therefore $ $ {v _{\max }}=\sqrt{\frac{2hv}{m}} $