Question

Electrons of 10 KeV strike a tungsten target. The radiations emitted by it are

• A. Visible light.
• B. X-rays.
• C. Infrared radiations.
• D. Radio waves.

Answer 1

The correct option is B X-rays.

Energy E $=10KeV=10\ast {10}^3\ast 1.6\ast {10}^{-19}J=1.6\ast {10}^{-15}J$
This energy is completely converted into radiation.
$E=h\nu$
i.e.
$\nu =\frac{E}{h}=\frac{1.6\ast {10}^{-15}}{6.63\ast {10}^{-34}}=2.413\ast {10}^{18}Hz$

The frequency obtained lies in the range of X rays.