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
Which of the following is the longest wave?
What is the cause of "Green house effect"?
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)?
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
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 charging current for a capacitor at any instant is 0.25 A.The displacement current across the capacitor plates at that instant is
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 ground state energy H-atom is 13.6 eV. The energy needed to ionize H –atom from its second excited state is