Dual Nature Of Light Question 398
Question: The work function for sodium surface is 2.0 eV and that for aluminum surface is 4.2 eV. The two metal are Illuminated with appropriate radiation so as to cause photoemission. Then
Options:
A) the threshold frequency for sodium will be less than that for aluminum
B) the threshold frequency for sodium will be more than that of aluminum
C) both sodium and aluminum will have the same threshold frequency
D) none of the above
Show Answer
Answer:
Correct Answer: A
Solution:
[a] As work function $ W=hv_{0}, $ , where $ v_{0} $ is the threshold frequency. Greater the work function, greater is the threshold frequency. Therefore, the threshold frequency of sodium will be lesser than that for aluminum.
BETA
