Question

If a source of power $4kW$ produces ${10}^{20}$ photons/second, the radiation belongs to a part of the spectrum called:-

• A. $\gamma$-rays
• B. $X$-rays
• C. Ultraviolet rays
• D. Microwave

Answer 1

The correct option is B $X$-rays

$4\times {10}^3={10}^{20}\times h\nu$

where $\nu =$frequency

$\nu =\frac{4\times {10}^3}{{10}^{20}\times 6.023\times {10}^{-34}}$

$\nu =6.64\times {10}^{16}Hz$

This frequency lies in the spectrum of X-rays.