Photoelectric threshold of silver is `lamda=3800A`. Ultraviolet light of `lamda=2600A` is incident of a silver surface. Calculate:
a. the value of work function in joule and in eV.
b. maximum kinetic energy of the emitted photoelectrons.
c. the maximum velocity of the photoelectrons.
(Mass of the electrons`=9.11xx10^(-31)`).

Options

A. `5.23xx10^(-19)J`
B. `6.5xx10^(-18)J`
C. `6.5xx10^(-19)J`
D. `5.5xx10^(-10)J`

Answer

A

Explanation

Here, `lamda_(0)=3800`Å
Work function `phi_(0)` or `W=hv_(0)=(hc)/(lamda_(0))`
`=(6.63xx10^(-34)xx3xx10^(8))/(3800xx10^(-10))`
`=5.23xx10^(-19)J` or `(3.2eV)`.