Question

The photo electric effect to take place for a metal, the minimum frequency required is 5.792 × 10¹⁴ Hz. A light of wavelength 6000 Å is incident on that metal surface. What is the corresponding frequency of light and will there be photoelectric emissions? [velocity of light = 3 × 10⁸ m/s]

Options

• 5 × 10¹⁴, yes

• 2 × 10¹⁴, no

• 20 × 10¹⁴, yes

• 5 × 10¹⁴, no

Answer 1

5 × 10¹⁴, no

Explanation:

v₀ = 5.792 × 10¹⁴ Hz

λ = 6000 Å = 6000 × 10^-10 m

∴ v = `(3 xx 10^8)/(6 xx 10^-7) = 1/2 xx10^15 = 0.5 xx 10^15`

= 5 × 10¹⁴ Hz

Since v < v₀ no photo electron possible.