Dual Nature Of Light Question 365
Question: The work functions of metals A and B are in the ratio 1 : 2. If light of frequencies f and 2f are incident on the surfaces of A and B respectively, the ratio of the maximum kinetic energies of photoelectrons emitted is (f is greater than threshold frequency of A, 2f is greater than threshold frequency of B)
Options:
A) 1 : 1
B) 1 : 2
C) 1 : 3
D) 1 : 4
Show Answer
Answer:
Correct Answer: B
Solution:
[b] $ E=W_{0}+{K_{\max }} $ …(i)
$ \Rightarrow hf=W_{A}+K_{A} $ …(ii) And $ 2hf=W_{B}+K_{B}=2W_{A}+K_{B} $ $ ( \therefore \frac{W_{A}}{W_{B}}=\frac{1}{2} ) $ Dividing equation (i) by (ii)
BETA
