51.

In the figure shown, if the diode forward voltage drop is 0.2 V, the voltage difference between A and B is

                   

• 2.2 V

• 1.3 V

• 0

• 0.5 V

Which of the following semi-conducting device is used as voltage regulator ?

• LASER diode

• Zener diode

• Solar cell

• Photo diode

Which of the following logic gate is universal gate ?

A particle is dropped from a height H. The de-Broglie wavelength of the particle depends on height as

• H^-1/2

• H⁰

• H^1/2

• H

In a system of two crossed polarisers, it is found that the intensity of light from the second polariser is half from that of first polariser. The angle between their pass axes is

• 60°

• 30°

• 0°

• 45°

During scattering of light, the amount of scattering is inversely proportional to ........ of wavelength of light.

• square

• fourth power

• half

• cube

The energy (in eV) required to excite an electron from n = 2 to n = 4 state in hydrogen atom is

• − 0.85 

• + 4.25

• − 3.4

• + 2.55

In a nuclear reactor, the function of the moderator is to decrease

• number of neutrons

• speed of neutrons

• escape of neutrons

• temperature of the reactor

The scientist who is credited with discovery of 'nucleus' in an atom is

• Rutherford

• Niels Bohr

• Balmer

• J J Thomson

In Young's double-slit experiment, if yellow light is replaced by blue light, the interference fringes becomes

• darker

• brighter

• wider

• narrower