If modulation index is 1/2 and power of carrier wave is 2 W. Then what will be the total power in modulated wave?
0.5 W
1 W
0.25 W
2.25 W
If velocity of a particle is three times of that of electron and ratio of de Broglie wavelength of particle to that of electron is 1.814 x 10-4. The particle will be
Neutron
Deuteron
Alpha
Tritium
In an intrinsic semiconductor band gap is 1.2 eV then ratio of number of charge carriers at 600 K and 300 K is
104
107
105
103
C.
105
We have formula
ni = n0 exp
wher KB - Boltzmann constant = 8.62 × 10-5 eV/K
T - temperature
n0 - constant
Initial temperature T1 = 300 K
The intrinsic carrier concentration at this temperature is written as
......(i)
Final temperature T2 = 600 K
The intrinsic carrier combination at this temperature is written as
........(ii)
The ratio between the conductivities at 600K and 300 K is equal to between the intrinsic carriers concentrations at these temperatures
= exp
=
= exp [11.6]
1.09 × 105 ≈ 105
Long distance communication between two point or earth is achieved by
Space wave communication
Sky wave communication
Satellite wave communication
Line of sight transmission
Polaroid glass is used in sun glasses because
it reduces the light intensity to half on account of polarisation
it is fashionable
it has good colour
it is cheaper
Which of the following statement is incorrect?
Neutron is less stable than proton
Neutron can cause fission in nuclear reactors but proton can not.
A free proton can emit beta particle.
A bound proton can emit beta particle.
Electric field at a distance r from infinitely long conducting sheet is proportional to
r-1
r-2
r-3/2
independent of r
In a Young's double slit experiment the spacing between the slits is 0.3 mm and the screen is kept at a distance of 1.5 m. The second bright fringe is found 6 mm from the central fringe. The wavelength of the light used in the experiment is
625 nm
600 nm
550 nm
500 nm
In beta plus decay
antineutrino is produced with electron
neutrino is produced with positron
neutron is produced with electron
none of these
The frequency of a light wave in a material is 2 × 1014 Hz and wavelength is 5000 Ao. The refractive index of material will be
1.50
3.00
1.33
1.40