Question

The frequencies of X-rays, $\gamma $-rays and ultraviolet rays are respectively p, q and r, then
A). p > q, q > r
B). p < q, q > r
C). p < q, q < r
D). p > q, q < r

Answer 1

Hint: The X-ray, gamma rays and ultraviolet rays are the shorter in the wavelength and the higher in energy. In the atmosphere of the Earth, the ultraviolet rays, gamma rays and x-rays are mainly blocked. It is blocked because these rays are the ionizing radiations. The x-rays, gamma rays and the ultraviolet rays add or remove the electrons from the molecules and give rise into the electrically charged ion.

Complete step by step solution:
The gamma rays, x-rays and the ultraviolet rays (few ultraviolet rays) have high energy that they are ionizing. It means they can remove electrons out of the atoms.
The x-rays have high energy. The x-rays pass along many materials, including our bodies. The different materials absorb the X- rays at the different levels. But x-rays are bad for us.
The gamma rays have the highest energy so their frequency is also highest because it is directly proportional to the Energy, and the frequency has the shortest wavelength because it is inversely proportional to the Energy.
The gamma rays released from the very high energy sources like neutron stars.
The gamma rays are also created by the Sun, but they don’t get away from the Sun, except from solar flares.
Here, p is the x – rays,
q is the gamma rays,
r is the ultraviolet rays.
The increasing order of the wavelength,
Gamma rays < x – rays > ultraviolet rays
Frequency order
Gamma rays > x – rays > ultraviolet rays
q > p , q > r
So, the option (B) is correct.

Note: In x-rays, our bones appear whites because the x-ray plate gets blackened. Our bones absorb x-rays more than the muscles so our bones show in an X-ray.
There are two types of the x-ray: one is soft x-ray, other is hard x-ray.
In soft x-ray, they lie between the ultraviolet rays and the gamma rays on the electromagnetic spectrum.
In hard x-ray, they lie in the same region as gamma rays.