The threshold frequency `V_0` for a metal is `7.0xx10^14 s^1`. Calculate the kinetic energy of an electron emitted when radiation of frequency `v=1.0xx10^15s^(-1)` hits the metal.

Explanation

According to Einstein’s equation Kinetic energy `=1//2m_eV^2=h(v-v_0)=(6.626xx10^(-34)Js)xx(1.0xx10^15s^-1-7.0xx10^14s^-1)=(6.626xx10^(-34)Js)xx(10.0xx10^14s^-1-7.0xx10^14s^-1)=(6.626xx10^(-34)Js)xx(3.0xx10^14s^-1)=1.988xx10^(-19)J`