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The maximum wavelength required to make possible photoelectric emission on a metal surface is irradiated with light f frequency 8.5 x 10^14 Hz. Determine: i. The threshold frequency. ii. The...

The maximum wavelength required to make possible photoelectric emission on a metal surface is irradiated with light f frequency 8.5 x 10^14 Hz.
Determine:
i. The threshold frequency.
ii. The work function of the metal in electron volts.
iii. The maximum kinetic energy f the electron.
Given that 1 eV = 1.6 x 10^-19J
Speed of light =3.0 x 10^8m/s
Plank’s constant h = 6.63 x 10^-34 Js

Answers


joseph
i. V =?f0
f0 =(3.0 x 10^8)/(8.0 x 10^-7)
= 3.75 x 10^14 Hz
ii. Work function = hf0
=6.63 x 10^-34 x 3.75 x10^14
=2.49 x 10^-19 J
In electron volt = (2.49 x 10^-19)/( 1.6 x 10^-19)
= 1.55eV
iii. K.E. MAX = hf – hf0
= 6.63 x 10^-34(8.5 – 3.75)
=3.149 x 10^-19 joules.

joseph rimiru answered the question on December 10, 2017 at 18:10

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