Physics interview questions

Saturation current are proportional to _____ of the radiation.

1. wavelength
2. velocity
3. intensities
4. frequency

The stopping potential depends upon the _____ of the fastest electron.

1. charge
2. frequency
3. wavelength
4. velocity

Electromagnetic theory could not explain

1. Polarisation
2. Diffraction
3. Photoelectric effect
4. Interference

_____ are used in obtaining electrical energy from sunlight during space travel.

1. Photoelectric cells
2. Lechlanche cells
3. Dry cells
4. Solar cells

____ deals with objects and systems, which are either moving at a constant speed with respect to one another or at the rest.

1. Millikan’s theory
2. Thomson’s theory
3. Special theory of relativity
4. Bohr’s theory

An instrument to magnify small objects is

1. Electron microscope
2. Radio telescope
3. Bragg’s spectrometer
4. None of the above

_____ cannot be focused using lenses.

1. Visible light
2. Infra-red rays
3. Sunlight
4. X-rays

At threshold frequency, stopping potential is

1. zero
2. infinity
3. positive
4. negative

The photoelectric emission is an _____ process.

1. radioactive
2. instantaneous
3. spontaneous
4. stimulated

____ is used in burglar alarm and fire alarm.

1. Photoelectric cell
2. Lechlanche cell
3. Dry cell
4. Solar cell

Identify the particle that has no rest mass.

1. Electron
2. Photon
3. Proton
4. Positron

_____ microscope is used to study bacteria, virus and structure of crystals.

1. X-ray
2. Simple
3. Optical
4. Electron

_____ is the basis for the electron microscope?

1. Particle nature of photon
2. Particle nature of proton
3. Wave nature of photon
4. Wave nature of electron

Maximum kinetic energy of photo electrons is independent of its

1. intensity
2. velocity
3. wavelength
4. frequency

Photoelectric effect indicates that light has the aspects of a particle

1. electron
2. neutron
3. proton
4. photon

Electrons accelerated in a particle accelerator with a very high velocity

1. acquires no mass variation
2. acquires infinite mass
3. acquires increased mass
4. acquires decreased mass

The wavelength of the matter wave is independent of

1. momentum
2. charge
3. velocity
4. mass

Work done in bringing the fastest electron to rest is equal to _____ energy of the fastest electron.

1. vibrational
2. rotational
3. potential
4. kinetic

_____ is the most commonly used semiconductor.

1. Germanium
2. Silicon
3. Both a and b
4. Neither a nor b

Collector current is usually measured in

1. milliamperes
2. microamperes
3. amperes
4. nanoamperes

The heavily doped region in a transistor is

1. base
2. collector
3. emitter
4. all the above

A transistor can be operated in how many types of circuit connections?

1. 1
2. 2
3. 3
4. 5

Photoelectric cell is a device which converts

1. light energy into electrical energy
2. electrical energy into light energy
3. kinetic energy into light energy
4. mechanical energy into sound energy

The photoelectric effect can be explained on the basis of

1. corpuscular theory of light
2. quantum theory of light
3. wave theory of light
4. electromagnetic theory of light

Maximum kinetic energy of photo electrons varies linearly with _____ of incident radiation.

1. wavelength
2. velocity
3. momentum
4. frequency

In electron microscope, the electron beam emitted by the filament is accelerated through a large potential difference in a device called

1. accelerator
2. electron gun
3. vandegraff generator
4. cyclotron

Smaller the wavelength, greater is the ____ power.

1. resolving
2. penetrating
3. diffusing
4. magnetic

Photon is a

1. particle
2. wave
3. neither a particle nor a wave
4. either a particle or a wave

Electron beam operates in _____ medium.

1. air
2. inert gas
3. vacuum
4. all of the above

At the threshold frequency, the velocity of the electrons is

1. maximum
2. minimum
3. infinite
4. zero