The waves which cannot travel in vacuum are
x-rays
radio waves
infrasonic waves
ultraviolet rays
The wave length of a radio wave of frequency of 1 MHz is
400 m
300 m
350 m
200 m
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
all of the above
All components of the electromagnetic spectrum in vacuum have the same
energy
velocity
wavelength
frequency
Electromagnetic waves are
transverse waves
longitudinal waves
produced by charges moving with constant velocity
none of the above
What is the cause of "Green house effect"?
Infrared rays
Ultraviolet rays
X-rays
Radio-waves
The structure of solids is investigated by using
Cosmic rays
Radio waves
Infrared radiations
Which of the following rays are not electromagnetic waves?
β-rays
Heat rays
Y-rays
Which one of the following electromagnetic radiations have the smallest wavelength?
Ultraviolet waves
Microwaves
The most energetic electromagnetic radiations are
microwaves
gamma rays
