Plz explain ... of wavelength 122 nm and stops the value of v is (mass of hydrogen atom 1.67 x 10-27 kg) o a. 3.25 m/sec b.

A hydrogen atom moving at a speed v absorbs a photon of wavelength 122 nm and stopS The value of v is (mass of hydrogen atom 1.67 x 10-27 kg) O A. 3.25 m/sec B. 6.25 m/sec O C. 9.25 m/sec D. 12.25 m/sec jee