In a plane electromagnetic wave, the electric field oscillates with a frequency of 2 × 1010 s-1 and an amplitude of 40 Vm-1. The wavelength of the wave is
3 × 10-3 m
2.5 × 10-2 m
1.5 × 10-2 m
4.5 × 10-3 m
The velocity of electromagnetic radiation in a medium of permittivity ε0 and permeability μ0 is given by
The frequency of y-rays, X-rays and ultraviolet rays are a, b and c respectively. Then
a>b>c
a
a=b-c
a>c>b
A signal emitted by an antenna from a certain point can be received at another point of the surface in the form of
Sky wave
Ground wave
Sea Wave
Both (a) and (b)
The frequency of electromagnetic wave, which is best suited to observe a particle of radius 3 × 10-4 cm, is of the order of
1015
1014
1013
1012
If a source is transmitting electromagnetic waves of frequency 8.2 × 106 Hz, then wavelength of the electromagnetic waves transmitted from the source will be
40.5m
42.3m
36.6m
50.9m
A TV tower has a height of 100 m. How much population is covered by the TV broadcast if the average population density around the tower is 1000 km-2 (radius of earth = 6370 km)?
4,00,000
4,000
40,000
40,000,00
Which one of the following electromagnetic radiations have the smallest wavelength?
X-rays
Y-rays
Microwaves
Ultraviolet rays
The amplitudes of electric and magnetic fields in an electromagnetic wave are related to each other as
E0 = B0
E0 = cB0
E0 = B0 /c
E0 = c/B
The structure of solids is investigated by using
Cosmic rays
Infrared radiation
