Second Year Physics Chapter 19 Online MCQ Test for 2nd Year Physics Chapter 19 Dawn of Modern Physics Preparation

Which one of the following physical quantities change with relativistic speed?

• Length A
• Time B
• Mass C
• All of above D

Internal frame is a frame is which

• 1st law holds A
• 2nd law holds B
• 3rd law holds C
• Kelvin's law holds D

In Compton effect the photon behaves as a.

• Wave A
• Particle B
• Nucleon C
• Both a and b D

Earth orbital speed is.

• 10 km/s A
• 20 km/s B
• 30 km/s C
• 40 km/s D

Wave nature of light appears in

• Pair production A
• Compton effect B
• Photo electric C
• Interference D

If the kinetic energy of a free electron doubles, its de Broglie wavelength changes by the factor.

• √2 A
• 1/√2 B
• 2 C
• 1/2 D

Unit of Stephen's constant is

• W m K^-2 A
• W m^-2 K^-4 B
• W m K^-4 C
• None D

The photon with energy greater than 1.02 MeV can interact with matter as.

• Photoelectric effect A
• Compton effect B
• Pair production C
• annihilation of matter D

The minimum frequency needed to emit an electron form metal surface is called:

• Work function A
• Threshold frequency B
• Quanta frequency C
• All of above D

• Wien's constant A
• Planck's constant B
• Davison constant C
• Lumber's constant D

The dimensions of Plank's constant is same as that of.

• Energy A
• Power B
• Acceleration C
• Angular momentum D

All motions are

• Absolute A
• Uniform B
• Relative C
• Variable D

Energy of Black body radiation depends upon

• Nature of surface of body A
• Nature of material of body B
• Shape and size of body C
• Temperature of the body D

In the equation if f₂ > then

• 
  A
• 
  B
• 
  C
• 
  D

The mass of an object will be doubled at speed.

• 2.6 x 10⁸ m/s A
• 1.6 x 10⁸ m/s B
• 2.6 x 10⁷ m/s C
• 3.6 x 10⁷ m/s D

Compton's effect is associated with

• gamma rays A
• Beta rays B
• X rays C
• Positive rays D

The wavelength associated with the protons moving at speed of 40 m/s is.

• 7.20 nm A
• 9.02 B
• 15.7 nm C
• 17.3 nm D