MCQs of Electromagnetic Waves

Electromagnetic Waves MCQs

MCQs of Electromagnetic Waves

Showing 21 to 30 out of 112 Questions

21.

A plane electromagnetic wave is travelling along the X - direction. The electric field vector at an arbitrary point at a time is

\vec{E} = 6.3 \overset{\land}{j} {Vm}^{- 1} .

The magnetic field at that point at that time is _____

(a)	$2.1 \times 10^{- 8} \overset{\land}{k} T$
(b)	$- 2.1 \times 10^{- 8} \overset{\land}{k} T$
(c)	$6.3 \overset{\land}{k} T$
(d)	$- 6.3 \overset{\land}{k} T$

22.

Unit of

\frac{E_{0}}{H_{0}}

is _____

(a)	A
(b)	Ω
(c)	V
(d)	Vm^-2

23.

Relative permittivity of a medium is 22.5 and its relative permeability is 0.1. Refractive index of medium is _____

(a)	0.67
(b)	1.4
(c)	1.5
(d)	1.8

24.

In electromagnetic waves the intensity of electric and magnetic field is respectively 100 Vm^-1 and 0.265 Am^-1 . Maximum intensity of energy is _____

(a)	26.5 Wm^-2
(b)	36.5 Wm^-2
(c)	46.7 Wm^-2
(d)	76.5 Wm^-2

25.

In a plane electromagnetic beam of intensity 4 Wm^-2 the amplitudes of electric field is _____ Vm^-1 .

(a)	5.5
(b)	55
(c)	5.5 × 10⁴
(d)	55 × 10⁴

26.

Radiated ray of maximum generation power is _____

(a)	γ - rays
(b)	β - rays
(c)	α - rays
(d)	X - rays

27.

The wavelength less than _____ Å almost all the electromagnetic waves are absorb in ozone layer.

(a)	4000 Å
(b)	3000 Å
(c)	5000 Å
(d)	6000 Å

28.

Dielectric constant of air is 1.005 and velocity of electromagnetic wave propogating in air is a × 10¹⁰ cm/s then a = _____

(a)	3
(b)	3.55
(c)	2.5
(d)	2.8

29.

Dimensional formula of

\frac{1}{μ_{0} ε_{0}}

is _____

(a)	M⁰L²T^-2
(b)	M¹L^-2T²
(c)	M⁰L^-1T¹
(d)	M⁰L¹T^-1

30.

If plane electromagnetic waves of momentum p and E are collied with the surface of any object then the value of p and E will be _____

(a)	p = 0, E = 0
(b)	p ≠ 0, E = 0
(c)	p = 0, E ≠ 0
(d)	p ≠ 0, E ≠ 0

Showing 21 to 30 out of 112 Questions