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

Question # 1

The special theory of relativity is based on the

one postulate A
two postulates B
three postulates C
four postulates D

Question # 2

Momentum is a parameter associated with

wave motion A
particle motion B
neither wave nor particle motion C
none of these D

Question # 3

The Nobel Prize on the explanation of photoelectric effect was awarded to:

Max. Planck A
Maxwell B
Bohr C
Rutherford D
None of these E

Question # 4

The general theory of relativity treats problems involving

inertial frame of references A
accelerating frame of references B
both of these C
none of these D

Question # 5

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

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

Question # 6

When a high energy photon interact with a metal, which of the following effect is most likely to be taken place

pair production A
photoelectric effect B
Compton effect C
None of these D

Question # 7

Newton's law of motion do not hold in

an accelerated frame of reference A
an unaccelerated frame of reference B
both of these C
none of these D

Question # 8

A photon is considered to have

Momentum A
Energy B
Wavelength C
All of the above D

Question # 9

The threshold frequency of sodium is 6 x 10⁶MHz. The cut-off wavelength for this metal will be

500 m A
500 nm B
500 km C
500 cm D
None of these E

Question # 10

The whole shape of the black body spectrum for all wavelengths was explained by the formula proposed by

Max plank A
Newton B
Einstein C
J.J. Thomson D

Question # 11

Practically the quantity v/c is always:

less than one A
Equal to one B
Greater then one C
all of these D
None of these E

Question # 12

When the atomic particle are moving with velocities approaching that of light:

Newton's laws become valid A
Relativistic effects become prominent B
Botha(A) and (B) are valid C
Neither (A)nor (B) D
There mass becomes zero. E

Question # 13

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

Remains constant A
Decreases B
Increases C
Reduces to zero D

Question # 14

The Einstein's changes in length, mass and time are not observed in common life because

We dont observer then seriously A
The masses are too large B
Their speed is too small than the speed of right C
All of the above D

Question # 15

The inside cavity of the black body is

painted white A
painted silver B
blackened with soot C
painted red D

Question # 16

According to the de-Brogile relation, an object of large mass and ordinary speed has

very small wavelength A
very large wavelength B
very small frequency C
all of these D

Question # 17

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 # 18

According to the electromagnetic wave theory of light, increasing the intensity of incident light should increase the

number of photoelectrons A
size of the photoelectrons B
charge on photoelectrons C
K.E of photoelectrons D

Question # 19

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 # 20

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 # 21

The energy of a photon in a beam of infrared radiation of wavelength 1240 nm is

100 ev A
10⁶e v B
10³e v C
1.0 e v D

Question # 22

The analysis of the distribution of wavelengths of the radiation emitted from a hot body set the foundation of new mechanics, known as

classical mechanics A
Newtonian mechanics B
quantum mechanics C
statistical mechanics D

Question # 23

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 # 24

The Stephen-Boltzmann law for the black body radiation is given by

E = T² A
E = -T² B
E = T⁴ C
E = -T⁴ D

Question # 25

In order to produce pair production, a photon must have a energy

0.511 Me v A
0.256 Me v B
1.02 Me v C
0.956 Me v D

Question # 26

If A represents linear momentum and c, the velocity of light, then unit of pc in international system of units is:

Newton A
Joule B
Joule-Sec C
Joule-s^-1 D
Watt E

Question # 27

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 # 28

The energy of the 4th orbit in hydrogen atom is

2.5 ev A
- 3.5 ev B
-0.85 ev C
-13.6 ev D

Question # 29

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

1916 A
1919 B
1921 C
1923 D

Question # 30

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

Sr.#	Question	Answer
1	The inside cavity of the black body is	A. painted white B. painted silver C. blackened with soot D. painted red
2	In process of annihilation of matter, the two photons produced move in opposite direction to converse	A. momentum B. charge C. energy D. mass
3	The general theory of relativity treats problems involving	A. inertial frame of references B. accelerating frame of references C. both of these D. none of these
4	de-Broglies hypthesis was experimentally verified by	A. Maxwell B. Compton C. Einstein D. Davison and Germer
5	The Einstein's changes in length, mass and time are not observed in common life because	A. We dont observer then seriously B. The masses are too large C. Their speed is too small than the speed of right D. All of the above
6	The stopping voltage for a certain metal is 100 volts, then the work function for the cathode plate is	A. 100 J B. 1.6 x 10^-17J C. 100 eV D. 1.6 x 10^-17eV
7	The special theory of relativity is based on the	A. one postulate B. two postulates C. three postulates D. four postulates
8	When a platinum wire is heated, it appears dull red at about	A. 500°C B. 900°C C. 1100°C D. 1300°C
9	A bar 1.0 m in length and located along x-axix moves with a speed of 0.75 c with respect to a stationary observer. The length of the bar as measured by the stationary observer is	A. 1.66 m B. 1.0 m C. 0.66 m D. 2.66 m
10	The energy of the 4th orbit in hydrogen atom is	A. 2.5 ev B. - 3.5 ev C. -0.85 ev D. -13.6 ev

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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

The special theory of relativity is based on the

Momentum is a parameter associated with

The Nobel Prize on the explanation of photoelectric effect was awarded to:

The general theory of relativity treats problems involving

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

When a high energy photon interact with a metal, which of the following effect is most likely to be taken place

Newton's law of motion do not hold in

A photon is considered to have

The threshold frequency of sodium is 6 x 106MHz. The cut-off wavelength for this metal will be

The whole shape of the black body spectrum for all wavelengths was explained by the formula proposed by

Practically the quantity v/c is always:

When the atomic particle are moving with velocities approaching that of light:

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

The Einstein's changes in length, mass and time are not observed in common life because

The inside cavity of the black body is

According to the de-Brogile relation, an object of large mass and ordinary speed has

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

According to the electromagnetic wave theory of light, increasing the intensity of incident light should increase the

The concept of direction is purely:

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

The energy of a photon in a beam of infrared radiation of wavelength 1240 nm is

The analysis of the distribution of wavelengths of the radiation emitted from a hot body set the foundation of new mechanics, known as

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

The Stephen-Boltzmann law for the black body radiation is given by

In order to produce pair production, a photon must have a energy

If A represents linear momentum and c, the velocity of light, then unit of pc in international system of units is:

The photon of radio-waves has energy of about

The energy of the 4th orbit in hydrogen atom is

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

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

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The threshold frequency of sodium is 6 x 10⁶MHz. The cut-off wavelength for this metal will be