ECAT Pre General Science Chapter 19 online mcq test with answers for Physics chapter 19 (Dawn of Modern Physics)

Question # 1

The location and speed anywhere on earth can now be determined using relativistic effects by NAVISTAR to an accuracy of

2 cm/s A
20 cm/s B
200 cm/s C
2000 cm/s D

Question # 2

The ratio of energy E to the corresponding frequency (f) of the radiation (emitted or absorbed) is called:

Wien's constant A
Stefen's constnat B
Planck's constant C
Boltzmann's constant D
None of these E

Question # 3

According to Einstein, with the great increase in the speed of the body, the relativistic mass of the body

Remains constant A
Decreases B
Increases to infinity C
Reduced to zero D

Question # 4

Electromagnetic radiation or photons interact with matter in

two distinct ways A
three distinct ways B
four distinct ways C
five distinct ways D

Question # 5

There is certain frequency below which no electrons are emitted from the metal surface, this frequency is known as

maximum frequency A
minimum frequency B
threshold frequency C
all of these D

Question # 6

Albert Einstein got the Nobel prize in physics for his explanation of photoelectric effect in

1916 A
1919 B
1921 C
1923 D

Question # 7

The stopping voltage for a certain metal is 100 volts, then the work function for the cathode plate is

100 J A
1.6 x 10^-17J B
100 eV C
1.6 x 10^-17eV D

Question # 8

Photoelectrons are emitted when ultraviolet light falls on:

Casium A
Silver B
Potassium C
Any of these D
None of these E

Question # 9

Which of the following is not an example of intertial frame

a body placed on the surface of earth A
a body placed in a car moving with uniform velocity B
a body placed in a car moving with same acceleration C
none of these D

Question # 10

A photon is considered to have

Momentum A
Energy B
Wavelength C
All of the above D

Question # 11

The speed of a pendulum is measured to be 3.0 s in the inertial reference frame of the pendulum. What is its period measured by an observer moving at a speed of 0.95 c with respect to the pendulum

2.9 s A
3.0 s B
6.6 s C
9.6 s D

Question # 12

The mass 'm' of a body moving at 0.8 c (whose rest mass is mo) becomes

2 mo A
1.67 mo B
0.67 mo C
2.67 mo D

Question # 13

The emission of electrons from a metal surface when exposed to light of suitable frequency is called the

pair production A
Compton effect B
photoelectric effect C
relativity D

Question # 14

The way through which electromagnetic radiations or photons interact with matter depends upon their:

Wavelength A
Frequency B
Energy C
Temperature D
All of these E

Question # 15

In process of annihilation of matter, the two photons produced move in opposite direction to converse

momentum A
charge B
energy C
mass D

Question # 16

Wien's constant is measured in:

Metre per kelviin A
Metre kelvin B
Kelvin per meter C
Joules D
Dynes E

Question # 17

Absolute motion cannot be detected

in its own frame of references A
in a different frame of references B
both in its frame and different frame of references C
none of these D

Question # 18

Max Planck received the Nobel Prize for his discovery of energy quants in:

1718 AD A
1918 AH B
1818 AD C
1918 AD D
None of these E

Question # 19

An intertial frame of reference is a frame of reference which is

at rest A
moving with uniform velocity B
either at rest or moving with uniform velocity C
none of these D

Question # 20

The idea of quantization of energy was proposed by:

Einstein A
Max.Planck B
Maxwell C
Bohr D
Rutherford E

Question # 21

A black body is

an ideal absorber A
an ideal radiator B
both of them C
none of them D

Question # 22

The concept of direction is purely:

Absolute A
Relative B
Relative to stars always C
Relative to the sun always D
None of these E

Question # 23

Victor de-Brogile received the Nobel prize in physics in

1925 A
1929 B
1932 C
1935 D

Question # 24

Which one of the following physical quantities changes with relativistic speed

Length A
Mass B
Time C
All of the above D

Question # 25

The photon of radio-waves has energy of about

1 Me V A
1 Ke v B
10^-10e v C
10¹⁰e v D

Question # 26

The nature of radiations emitted by a hot body depends upon its:

Metarial A
Temperature B
colour C
Volume D
Length E

Question # 27

The year when A.H. compton was awarded Nobel Prize is:

1923 A
1927 B
1931 C
1935 D
None of these E

Question # 28

According to the special theory of relativity, time is

absolute quantity A
not absolute quantity B
constant quantity C
none of these D

Question # 29

Due to relative motion of observer and the frame of reference of events, time always:

Dilates itself A
Contracts itself B
Stretches itself C
Both (A) and (C) D
None of these E

Question # 30

de-Broglies hypthesis was experimentally verified by

Maxwell A
Compton B
Einstein C
Davison and Germer D

Sr.#	Question	Answer
1	S.I. unit of planks constant is	A. J-s^-1 B. J.s C. J.s^-2 D. J.s²
2	G.P. Thomson observer experimentally that electrons and neutrons possess	A. particle-like properties B. wave-like properties C. neither particle nor wave like properties D. none of these
3	The idea of quantization of energy was proposed by:	A. Einstein B. Max.Planck C. Maxwell D. Bohr
4	According to Einstein, with the great increase in the speed of the body, the relativistic mass of the body	A. Remains constant B. Decreases C. Increases to infinity D. Reduced to zero
5	The energy of a photon in a beam of infrared radiation of wavelength 1240 nm is	A. 100 ev B. 10⁶e v C. 10³e v D. 1.0 e v
6	Due to relative motion of observer and the frame of reference of events, time always:	A. Dilates itself B. Contracts itself C. Stretches itself D. Both (A) and (C)
7	When low energy photon interact with a metal,which of the following effect is likely to be taken place	A. pair production B. photoelectric C. Compton effect D. None of these
8	The ratio of energy E to the corresponding frequency (f) of the radiation (emitted or absorbed) is called:	A. Wien's constant B. Stefen's constnat C. Planck's constant D. Boltzmann's constant
9	The emission of electrons from a metal surface when exposed to light of suitable frequency is called the	A. pair production B. Compton effect C. photoelectric effect D. relativity
10	The threshold frequency of sodium is 6 x 10⁶MHz. The cut-off wavelength for this metal will be	A. 500 m B. 500 nm C. 500 km D. 500 cm

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ECAT Pre General Science Physics Chapter 19 MCQ Test With Answer

MCQ's Test For ECAT Pre General Science Physics Chapter 19 Dawn of Modern Physics

ECAT Pre General Science Physics Chapter 19 Dawn of Modern Physics