Modern Physics Multiple Choice Questions with Answers – PDF Download

Rest mass energy of an electron is

1. 1.02 MeV
2. 0.511KeV
3. 0.511 MeV
4. 2.02 MeV

When K.E_max of photoelectrons is zero, then the frequency of incident photon relative to threshold frequency is

1. less
2. equal
3. greater
4. small

An inertial frame of reference is the frame

1. in which first law of motion is valid
2. in which law of inertia is valid
3. which is not moving with uniform velocity
4. both a and b

In photocell caesium, coated oxidized silver cathode emits electrons for

1. visible light
2. ultraviolet
3. infrared light
4. x-rays

According to the theory of relative mass of an object is

1. depends on particles
2. speed of light
3. volume of object
4. area of object