A hydrogen atom moving at a speed v absorbs a photon of wavelength 122 nm and stops. The value of v is -

Question

A hydrogen atom moving at a speed v absorbs a photon of wavelength 122 nm and stops. The value of v is - (A) 2.75 m / s (B) 3.25 m / s (C) 4.85 m / s (D) 5.65 m / s

Tardigrade Admin · Accepted Answer

Linear momentum of photon and electron are equal and opposite

p = m v = \frac{h}{λ}

, where

m, v, h & λ

represents mass, velocity, Plank's constant and wavelength respectively.

v = \frac{h}{mλ} = \frac{6.62 \times 1 0 ^{- 34}}{1.67 \times 1 0 ^{- 27} \times 122 \times 1 0 ^{- 9}}

v = 3.25 m / s

Q. A hydrogen atom moving at a speed $v$ absorbs a photon of wavelength $122 nm$ and stops. The value of $v$ is -

$2.75 m / s$

$3.25 m / s$

$4.85 m / s$

$5.65 m / s$

Q. A hydrogen atom moving at a speed v absorbs a photon of wavelength 122nm and stops. The value of v is -

2.75m/s

3.25m/s

4.85m/s

5.65m/s

Linear momentum of photon and electron are equal and opposite p=mv=λh​ , where m,v,h&λ represents mass, velocity, Plank's constant and wavelength respectively. v=mλh​=1.67×10−27×122×10−96.62×10−34​ v=3.25m/s

Q. A hydrogen atom moving at a speed $v$ absorbs a photon of wavelength $122 nm$ and stops. The value of $v$ is -

$2.75 m / s$

$3.25 m / s$

$4.85 m / s$

$5.65 m / s$