The threshold frequency of metal is f₀. When the light of frequency 2f₀ is incident on the metal plate, the maximum velocity of photoelectron is v₁. When the frequency of incident radiation is increased to 5f₀ the maximum velocity of photoelectrons emitted is v₂. The ratio v₁ to v₂ is (a) 1: 2 (b) 1: 8 (c) 1: 16 (d) 1: 4

Answer: (a). 1/2mv² = hν - hν₀ At 2ν₀: K₁ = hν₀; at 5ν₀: K₂ = 4hν₀ (v₁)/(v₂) = √(1/4) = 1/2 So the answer is (a) 1: 2.

The threshold frequency of metal is f₀. When the light of frequency… | MHT CET 2026 (13 Apr, Shift 2)

Q22MHT CET 2026 · 13 APR · SHIFT 2Medium

Photoelectric Effect: Einstein's Equation

The threshold frequency of metal is $f_0$ . When the light of frequency $2f_0$ is incident on the metal plate, the maximum velocity of photoelectron is $v_1$ . When the frequency of incident radiation is increased to $5f_0$ the maximum velocity of photoelectrons emitted is $v_2$ . The ratio $v_1$ to $v_2$ is

Show answer and solution

Answer: (a)

$\frac{1}{2}mv^2 = h\nu - h\nu_0$
At $2\nu_0$ : $K_1 = h\nu_0$ ; at $5\nu_0$ : $K_2 = 4h\nu_0$
$\frac{v_1}{v_2} = \sqrt{\frac{1}{4}} = \frac{1}{2}$
So the answer is (a) $1 : 2$ .

Report a mistake

Photoelectric Effect: Einstein's Equation question from MHT CET 2026 (13 Apr, Shift 2)

More questions on Photoelectric Effect: Einstein's Equation