The energy of the EM wave is of the order of \(15\) KeV. To which part of the spectrum does it belong?
1. X-rays
2. Infrared rays
3. Ultraviolet rays
4. Y-rays

Which colour of the light has the longest wavelength?
1. violet
2. red
3. blue
4. green

1. \(A\) and \(B\) only
2. B and \(C\) only
3. \(A,B,\) and \(C\) only
4. \(B\) only

Which of the following electromagnetic waves has minimum frequency?
1. Radio waves
2. Infrared waves
3. Microwaves
4. X-rays

The shortest wavelength is for 

(1) $\gamma$-rays

(2) X-rays

(3) ultraviolet rays

(4) microwaves

The electromagnetic radiations are in descending order of wavelength in the following sequences :

(1) infra-red waves, radio waves, X-rays, visible light rays

(2) Radio-waves, infra-red waves, visible light rays, X-rays

(3) Radio waves, visible light rays, infra-red waves, X-rays

(4) X-rays, visible light rays, infra-red wave, radio-waves

Which of the following are not electromagnetic waves?

(1) cosmic rays

(2) gamma rays

(3) microwaves

(4) X-rays

The wave impedance of free space is

(1) 0 $\Omega$

(2) 376.6 $\Omega$

(3) 1883 $\Omega$

(4) 3776 $\Omega$

The frequency 1057 MHz of radiation arising from two close energy levels in hydrogen belongs to

(1) radio waves

(2) infrared waves

(3) micro waves

(4) $\gamma$-rays