Threshold frequency for platinum is 1.3×1015 sec-1. Platinum shows photo electric effect when exposed to

Threshold frequency of platinum falls in the U V range ( 8×1014 s-1 - 3 ×1016 s -1). Platinum display the photo electric effect when exposed to U V light  pt frequency ⩾ 1.3 ×1015 s-1Frequency of I R light is in the range of 1012 s-1 - 4 × 1014 s-1 lesser the threshold frequency of platinum, will not show photo electric effect.