1.

Threshold frequency for photosensitive material is v_(0). If photons of frequency 2v_(0) fall on this surface, the electrons come out with a maximum speed of 4xx10^(6)ms^(-1). When photons of frequency 5v_(0) fall on the same surface, the maximum speed of the ejected electrons will be

Answer»

`2xx10^(7)ms^(-1)`
`2xx10^(6)ms^(-1)`
`8XX10^(6)ms^(1)`
`8xx10^(5)ms^(-1)`

Solution :As per relation `h(v-v_(0))=(1)/(2)mv_(max)^(2)`, we have
`((v_(1))_(max))/((v_(2))_(max))=SQRT((v_(1)-v_(0))/(v_(2)-v_(0)))=sqrt((2v_(0)-v_(0))/(5v_(0)-v_(0)))=1/2 implies (v_(2))_(max)=2(v_(1))_(max)=2xx4xx10^(6)=8xx10^(6)ms^(-1)`.


Discussion

No Comment Found

Related InterviewSolutions