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

Which one of the following paved the way for modern physics

• Newtonian mechanics A
• Theory of relativity B
• Quantum theory C
• All of above D

By modern system of NAVSTAR, the speed any where on the earth can be determined to accuracy about.

• 20 ms-1 A
• 10 ms-1 B
• 2 cms-1 C
• 2 ms-1 D

Eintein's Photoelectric equation is E_k= hf -∅ in this equation E₁, refers to:

• K.E of al the emited electrons A
• Mean K.E of emited electrons B
• Maximum K.E of emited electrons C
• Minimum K.E of emited electrons D

Compton effect proves.

• Wave nature of radiation A
• Wave nature of particle B
• Dual nature of particle C
• Particle nature of radiations D

Anti particle of electron is

• Proton A
• Photon B
• Neutron C
• Positron D

The position has charge which is in magnitude equal to the charge on

• Electron A
• Proton B
• β particle C
• All D

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

When platinum is heated is become dull red at:

• 900°C A
• 500°C B
• 800°C C
• 1100°C D

The stopping potential for a certain metal is 10 volts. Thus work function for the cathode is.

• 10 J A
• 1.6 X 10^-18 J B
• 1.6 X 10^-19 J C
• 1.6 X 10³⁰ J D

Disintegration of photon on striking a nucleus into an electron and positron is known as.

• Annihilation of matter A
• Compton effect B
• Pair production C
• Photo electric effect D

The existence of positron was discovered in:

• 1929 A
• 1928 B
• 1931 C
• 1933 D

When platinum is it becomes orange at

• 500^oC A
• 900^oC B
• 1100^oC C
• 1300^oC D

Pair production can take place only when energy of radiation is equal and greater than 1.02 MeV, thus correct option is.

• X rays A
• Gama rays B
• Heat Radiation C
• Ultraviolet rays D

All motions are

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

In Compton effect the photon behaves as a.

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

Minimum energy needed to escape an electron  ofrm metal surface is called:

• Threshold energy A
• Threshold frequency B
• Work function C
• Work ability D

Platinum wire becomes yellow at a temperature of.

• 900 ^oC A
• 1300^oC B
• 1600^oC C
• 500^oC D