Question

The momentum of the photon of wavelength 5000Å will be-

• A. 1.3 × 10^–27 kg m/s
• B. 1.3 × 10^–28 kg m/s
• C. 4 × 10²⁹ kg m/s
• D. None of these

Answer 1

Answer: (A)

1.3 × 10^–27 kg m/s

Answer 2

p =

p = $\frac { 6.6 \times 10 ^ { - 34 } } { 5000 \times 10 ^ { - 10 } }$ = 1.3 × 10^{–34 + 10 – 3}

p = 1.3 × 10^–27 kg m/s