The kinetic energy of the electron emitted when light of frequency 3.5 ×1015 Hz falls on a metal surface having threshold frequency 1.5 × 1015 Hz is (h = 6.6 × 10-34 Js

Question

The kinetic energy of the electron emitted when light of frequency 3.5 ×1015 Hz falls on a metal surface having threshold frequency 1.5 × 1015 Hz is (h = 6.6 × 10-34 Js (A) 1.32 × 10-18J (B) 3.3 × 10-18J (C) 6.6 × 10-19 J (D) 1.98 × 10-19J

Tardigrade Admin · Accepted Answer

KE=h (v-vo) = 6.6 ×10-34 (3.5 ×1015-1.5×1015) =1.32 ×10 -18 J

Q. The kinetic energy of the electron emitted when light of frequency $3.5 \times 1 0^{15}$ Hz falls on a metal surface having threshold frequency $1.5 \times 1 0^{15}$ Hz is ( $h = 6.6 \times 1 0^{- 34}$ Js

$1.32 \times 1 0^{- 18}$ J

$3.3 \times 1 0^{- 18}$ J

$6.6 \times 1 0^{- 19}$ J

$1.98 \times 1 0^{- 19}$ J

$K E = h (v - v_{o})$
$= 6.6 \times 1 0^{- 34} (3.5 \times 1 0^{15} - 1.5 \times 1 0^{15})$
$= 1.32 \times 1 0^{- 18} J$

Q. The kinetic energy of the electron emitted when light of frequency 3.5×1015 Hz falls on a metal surface having threshold frequency 1.5×1015 Hz is (h=6.6×10−34 Js

1.32×10−18J

3.3×10−18J

6.6×10−19 J

1.98×10−19J