The threshold frequency `v_(0)` for a metal is `7xx10^(14)s^(-1)` . Calculate the kinetic energy of an electron emitted when radiation of frequency `v = 1.0 xx 10^(15)s^(-1)` hits the metal .

Explanation

According to Einstein's equation, K.E. of the photoelectron emitted `((1)/(2) mv^(2))`
`= h (v - v_(0)) = (6.626 xx 10^(-34) Js) (1.0 xx 10^(15) s^(-1) - 7.0 xx 10^(14) s^(-1))`
`= (6.626 xx 10^(-34)Js) (3 xx 10^(14) s^(-1)) = 19.88 xx 10^(-20) J or 1.988 xx 10^(-19) J`