The frequency order for \(\gamma\) - rays (\(b\)), X – rays (\(a\)), and UV – rays (\(c\)) is:

1.	\( b>a>c \)	2.	\( a>b>c \)
3.	\( c>b>a \)	4.	\( a>c>b\)

If \(\lambda_{\mathrm{v}}, \lambda_{\mathrm{x}},\) and\(\lambda_\mathrm{m}\) represent the wavelengths of visible light, x-rays and microwaves respectively, then:
1. \( \lambda_{\mathrm{m}}>\lambda_{\mathrm{x}}>\lambda_{\mathrm{v}} \)
2. \( \lambda_\mathrm{v}>\lambda_\mathrm{m}>\lambda_\mathrm{x } \)
3. \( \lambda_\mathrm{v}>\lambda_\mathrm{x}>\lambda_\mathrm{m }\)
4. \(\lambda_{\mathrm{m}}>\lambda_{\mathrm{v}}>\lambda_{\mathrm{x}}\)

Which of the following has the minimum wavelength?
1. X-rays
2. Ultraviolet rays
3. γ-rays
4. Cosmic rays

What is the cause of “Greenhouse effect”?

1. Infra-red rays

2. Ultraviolet rays

3. X-rays

4. Radio waves

The ratio of the amplitude of a magnetic field to the amplitude of an electric field for an electromagnetic wave propagating in a vacuum is equal to:

The magnetic field in a plane electromagnetic wave is given by:
\(B_y = 2\times10^{-7} \text{sin}\left(\pi \times10^{3}x+3\pi\times10^{11}t\right )T\)${}_{}$
The wavelength is:
1. \(\pi\times 10^{3}~\text{m}\)
2. \(2\times10^{-3}~\text{m}\)
3. \(2\times10^{3}~\text{m}\)
4. \(\pi\times 10^{-3}~\text{m}\)

The EM wave with the shortest wavelength among the following is:

Which of the following is not an electromagnetic wave?

1. Radio wave

2. Micro wave

3. Cosmic rays

4. $\mathrm{\gamma }$-rays

If an electromagnetic wave propagating through vacuum is described by \(E_y= E_0 sin(kx-\omega t); ~B_z= B_0sin(kx-\omega t),\)then:
1. \(E_0k=B_0\omega\)
2. \(E_0B_0 = \omega k\)
3. \(E_0\omega= B_0k\)
4. \(E_0B_0= \frac{\omega}{k}\)