Question

The momentum of a photon having frequency

1.0 × 10¹⁵ s^–1 is about

• A. 2.21 × 10^–11 kg m s^–1
• B. 2.21 × 10^–27 kg m s^–1
• C. 2.21 × 10^–19 kg m s^–1
• D. 6.63 × 10^–19 kg m s^–1

Answer 1

Answer: (B)

2.21 × 10^–27 kg m s^–1

Answer 2

P = $\frac{h}{\lambda}$ = $\frac{h}{C}$ × n

= $\frac{(6.6 \times 10^{–34}Js)(10^{15}s^{–1})}{(3 \times 10^{8}ms^{–1})}$

= 2.21× 10^–27 kg ms^–1