Which of the following phenomenon is not common to sound and light waves?
interference
diffraction
coherence
polarisation
The frequency of electromagnetic wave, which is best suited to observe a particle of radius 3 × 10-4 cm, is of the order of
The charging current for a capacitor at any instant is 0.25 A.The displacement current across the capacitor plates at that instant is
Which of the following rays are not electromagnetic waves?
β-rays
Heat rays
X-rays
y-rays
A signal emitted by an antenna from a certain point can be received at another point of the surface in the form of
both (a) and (b)
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 frequency of y-rays, X-rays and ultraviolet rays are a, b and c respectively. Then
If λv, λx and λm represent the wavelengths of visible light, X-rays and microwaves respectively, then
λm > λx > λv
λv > λm > λx
λm > λv > λx
λv > λx > λm
Which of the following is the longest wave?
Electromagnetic waves are
transverse waves
longitudinal waves
produced by charges moving with constant velocity
none of the above
