Which one of the following electromagnetic radiations have the smallest wavelength?
X-rays
Y-rays
Microwaves
Ultraviolet rays
Ozone layer blocks the radiations of wave length
less than 3 × 10-7 m
equal to 3 × 10-7 m
more than 3 × 10-7 m
None of these
The velocity of electromagnetic radiation in a medium of permittivity ε0 and permeability μ0 is given by
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 of the following is the longest wave?
x-rays
y-rays
Radiowaves
Electromagnetic waves are
transverse waves
longitudinal waves
produced by charges moving with constant velocity
none of the above
The velocity of electromagnetic wave is along the direction of
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
What is the cause of "Green house effect"?
Infra red 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
