MCQ
For harder X-rays:
- AThe wavelength is higher.
- BThe intensity is higher.
- CThe frequency is higher.
- DThe photon energy is higher.
✓
Answer
- The frequency is higher.
- The photon energy is higher.
Explanation:
Harder X-rays are the X-rays having low wavelengths. Since the frequency varies inversely with the wavelength, hard X-rays have high frequency.
Energy of a photon (E) is given by
$\text{E}=\frac{\text{hc}}{\lambda}$
Here,
h = Planck's constant
c = Speed of light
$\lambda$ = Wavelength of light.
Clearly, energy varies inversely with wavelength. Therefore, the energy of the photon will be higher for the hard X-ray.
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