Photoelectric effect is obtained on metal surface for a light having frequencies f1 & f2 where f1 > f2. If ratio of maximum kinetic energy of emitted photo electrons is 1:K, so threshold frequency for metal surface is…………
(A) {(f1 – f2) / (K – 1)}
(B) {(Kf1 – f2) / (K – 1)}
(C) {(K f2 – f1) / (K – 1)}
(D) {(f2 – f1) / K}