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

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

  • Total Questions30

  • Time Allowed30

Start Test Download PDF

ECAT Pre General Science Physics Chapter 19 Dawn of Modern Physics

00:00
Question # 1

When monochromatic light is allowed to fall on cathode, it begins to emit electrons, these electrons are called

Question # 2

The special theory of relativity is based on the

Question # 3

As compared to the distance measured by an observer on Earth, the distance from Earth to a star measured by an observer in a moving spaceship would seem:

Question # 4

The unit of work function is:

Question # 5

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

Question # 6

Which of the following is not an example of intertial frame

Question # 7

Intensity of light determines the:

Question # 8

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

Question # 9

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

Question # 10

When a position comes close to an electron they annihilate into

Question # 11

The length contraction happens only

Question # 12

Electromagnetic -radiation means:

Question # 13

The concept of direction is purely:

Question # 14

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

Question # 15

Compton studied the scattering of x-rays by loosely bound electrons from:

Question # 16

Compton was awarded Nobel prize in physics in

Question # 17

A particle of mass 5.0 mg moves with a speed of 8.0 m/s. Its de-Brogile wavelength is

Question # 18

Compton shift refers to:

Question # 19

A photon is considered to have

Question # 20

If the radius of first orbit of hydrogen atom is 0.53° A the radius of second orbit will be

Question # 21

Which of the following phenomenon proves the particle nature of light

Question # 22

The photoelectric effect, the maximum energy of photoelectrons depends on the

Question # 23

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

Question # 24

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

Question # 25

When a platinum wire is heated, it appears dull red at about

Question # 26

According to the special theory of relativity

Question # 27

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

Question # 28

An inertial frame is that frame in which

Question # 29

According to the special theory of relativity, time is

Question # 30

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

Submit

Prepare Complete Set Wise ECAT Pre General Science Physics Chapter 19 Dawn of Modern Physics MCQs Online With Answers


Topic Test

00:00
Submit

Top Scorers Of ECAT Pre General Science Physics Chapter 19 Dawn of Modern Physics MCQ`s Test

  • A
    Asghar Ali 03 - Mar - 2021 10 Min 50 Sec 100/120
  • S
    shamsuddin 19 - Aug - 2021 10 Min 50 Sec 75/120
  • K
    khadim Hussain 03 - Mar - 2021 10 Min 50 Sec 75/120
  • A
    Ali ahmad 19 - Jul - 2018 09 Min 44 Sec 70/120
  • A
    Aarij 08 - Dec - 2024 02 Min 25 Sec 65/120
  • W
    Waleed Ahmed 26 - Feb - 2023 10 Min 00 Sec 65/120
  • Z
    Ziyad Rehman Sheikh 16 - Nov - 2022 07 Min 21 Sec 40/120
  • M
    maha 01 - Mar - 2023 04 Min 24 Sec 35/120

ECAT Physics Chapter 19 Important MCQ's

Sr.# Question Answer
1 According to Einstein, with the great increase in the speed of the body the relativistic length of the body
A. Remains constant
B. Decreases
C. Increases
D. Reduces to zero
2 The unit of work function is:
A. Joule
B. Electron volt
C. That of threshold frequency
D. Both (A) and (B)
3 The Nobel Prize on the explanation of photoelectric effect was awarded to:
A. Max. Planck
B. Maxwell
C. Bohr
D. Rutherford
4 The mass 'm' of a body moving at 0.8 c (whose rest mass is mo) becomes
A. 2 mo
B. 1.67 mo
C. 0.67 mo
D. 2.67 mo
5 The value of the plank's constant 'h' is given by
A. 1.6 x 10-19J
B. 1.67 x 10-27Kg
C. 6.63 x 1034Js
D. 6.63 x 10-34Js
6 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
7 When a platinum wire is heated, it appears white at
A. 1600°C
B. 900°C
C. 1100°C
D. 1300°C
8 An inertial frame is that frame in which
A. a>0
B. a=0
C. a<0
D. none of these
9 The concept of direction is purely:
A. Absolute
B. Relative
C. Relative to stars always
D. Relative to the sun always
10 The energy of a photon is represented by
A. h/c2
B. h/T
C. hc2
D. hf/c2

Test Questions

Is this page helpful?