Question

Find the cutoff wavelength for the continuous X-rays coming from an X-ray tube operating at 30 kV.

Answer 1

The cutoff wavelength for the continuous X-rays coming from an X-ray tube operating at 30 kV is 41.4pm.

• Given that : Continuous rays are coming from an X-ray tube operating at 30kV.

• We know that, Cutoff wavelength of an electromagnetic waveguide is the maximum wavelength for which a mode will propagate in it and it is given by,

wavelength = hc/E = hc/eV

• Hence, using the above formula, we get-

Required wavelength = hc/eV

= 1242eV*nm/ e*30*10^3

= 414*10^-4 nm

= 414 pm

Answer 2

The cutoff wavelength is 41.4 pm for the continuous x-rays.

Explanation:

In the question, it is given that

X-ray tube’s voltage, V = 30 kV

For continuous x-rays cutoff wavelength, λ is shown as $\lambda=\mathrm{h} \cos \mathrm{V}$

Here, h = Constant of Planck

V = X-ray tube’s voltage

c = light’s speed

Therefore, $\lambda=1242 \mathrm{eV}-\mathrm{nme} \times 30 \times 10^{3}$

$\Rightarrow \lambda=414 \times 10^{-4} \mathrm{nm}$

=41.4 pm