1 Ao =
10-8 cm
10-9 cm
10-10 cm
10-11 cm
Which one of the following electromagnetic radiations have the smallest wavelength?
X-rays
Y-rays
Ultraviolet waves
Microwaves
The wave length of a radio wave of frequency of 1 MHz is
400 m
300 m
350 m
200 m
Mapping of the radio emissions from extra-terrestrial sources is known as ________________.
Radiography
Radio-astronomy
Seiesmography
None of these
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
Which of the following has minimum wavelength?
Ultraviolet rays
Cosmic rays
The structure of solids is investigated by using
Radio waves
Infrared radiations
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
Which of the following is the longest wave?
Radiowaves
Which of the following rays are not electromagnetic waves?
β-rays
Heat rays