ECAT Pre General Science Chapter 20 online mcq test with answers for Physics chapter 20 (Atomic Spectra)

Question # 1

Photons must have energy equal to

ev A
En B
hf C
None of these D

Question # 2

The results of spectra obtained by Blamer were expressed in 1896 by

Bohr A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 3

Selenium is:

An insulator A
A conductor B
Both A and B C
Excellent conductor D
None of these E

Question # 4

Spectrum represents the number of component colours present in certain light in terms of:

Wavelength A
Frequency B
Energy C
Both (A) and (B) D
All of these E

Question # 5

In flesh, light element like carbon, hydrogen and oxygen predominate. Three elements allows ______ amount of incident X-ray to pass through them

Small A
Greater B
Equal C
Sometimes D

Question # 6

Atoms of hydrogen gas can be excited by passing electric current through it when the gas is filled into the discharge tube at a pressure which is

Less than atmospheric pressure A
Much less than atmospheric pressure B
Greater than atmospheric pressure C
Much greater than atmospheric pressure D
Both C and D E

Question # 7

The transitions of electrons in the hydrogen atom result in the emission of spectral lies in the:

Ultra red region A
Visible region B
Ultraviolet region C
Any of these D
None of these E

Question # 8

Consider a photon of continuous X-ray and a photon of characteristics X-ray of same wavelength. Which of the following is/are different for the two photons

Frequency A
Penetrating power B
Energy C
Method of creation D

Question # 9

X-rays can penetrate in a solid matte through a distance of several:

Kilo metres A
Metres B
Centimeters C
A few angstroms D
One micrometer E

Question # 10

The lasing or active medium in He-Ne laser discharge tube is:

Nitrogen A
Helium B
Hydrogen C
Neon D
None of these E

Question # 11

An electron of the hydrogen atom in the second orbit is called its:

Ground state A
Excited state B
Ionized state C
Any of these D
None of these E

Question # 12

The inkjet printer eject a thin stream of:

Water A
Oil B
Ink C
Any above D
None of these E

Question # 13

By CAT scans, we can detect the density difference of the order of:

1% A
20% B
30% C
50% D
70% E

Question # 14

Laser is a beam of:

Visible light A
Infra red light B
Ultra violet light C
Violet light only D
yellow light only E

Question # 15

Static electricity is produced by the transfer of:

Electrons A
Protons B
One fluid C
Two fluid D
None of these E

Question # 16

In case of braking radiations, when the rate of deceleration is very large, the emitted radiation corresponds to:

Short wavelength A
Large wavelength B
Very large wavelenth C
Low frequency D
Both (B) and (C) E

Question # 17

The He-Ne laser discharge tube is filled with:

85% He A
15% He B
50% He C
60% He D
85% Ne E

Question # 18

Lyman series in the spectrum of hydrogen exists in the :

Infra-red region A
Visible region B
Ultraviolet region C
Both(A) and (B) D
None of these E

Question # 19

If the distance between two charges is doubled,the force between them will become:

Double A
Half B
One third C
One fourth D

Question # 20

An compared to solid matter, a crack or an air bubble allows:

Great amount of X-rays to pass A
Smallast amount of X-rays to pass B
Very samall amount of X-rays to pass C
Any of these D
None of these E

Question # 21

The photocopying process is called:

Geography A
Sonography B
Xerography C
Zerography D
None of these E

Question # 22

The holes created in the L and M shells are occupied by transitions of:

Electrons from lower states A
Electrons from higher state B
Positrons from higher states C
Electrons from K shell D
Both (A) and (B) E

Question # 23

A metastable stae:

Is an excited state A
Is that in which excited electron is stable B
Is that in which excited electron is usually unstable C
Means a time interval of 10^-8second D
Both (A) and (C) E

Question # 24

The value of the metastable state for Neon is

20.66eV A
20.61eV B
19.23eV C
18.70eV D

Question # 25

Gaussian surface is always:

Rectangular A
Spherical B
Cylinder C
Box shape D
Any of these E

Question # 26

The life time of metastable state is equal to

Life time of excited state A
Greater than by excited state B
Zero C
Less than by excited state D

Question # 27

Tick the series which lie/s in. the infra-red region.

Pfund series A
Brackett series B
Paschen series C
All of these D
None of these E

Question # 28

We can excite an atom by

Bombardment of particles A
Radiating photons B
Providing potential difference C
All answer are true D

Question # 29

X-ray are also known as

Roentgen rays A
Maxwell rays B
Plank range C
Einstein rays D

Question # 30

Graph of Black body radiation is example of

Band spectra A
Continuo's spectra B
Line spectra C
All D

Sr.#	Question	Answer
1	X-ray are also known as	A. Roentgen rays B. Maxwell rays C. Plank range D. Einstein rays
2	Tick the series which lies in the visible region:	A. Lyman series B. Balmer series C. Paschen series D. Brackett series
3	The photocopying process is called:	A. Geography B. Sonography C. Xerography D. Zerography
4	The first shell near the neucles is	A. L-shell B. X-shell C. N-shell D. M-shell
5	Gaussian surface is always:	A. Rectangular B. Spherical C. Cylinder D. Box shape
6	Ultraviolet region lies in ______ series	A. Layman B. Balmer C. P fund D. B racket
7	The lasing or active medium in He-Ne laser discharge tube is:	A. Nitrogen B. Helium C. Hydrogen D. Neon
8	The inkjet printer eject a thin stream of:	A. Water B. Oil C. Ink D. Any above
9	The life time of metastable state is equal to	A. Life time of excited state B. Greater than by excited state C. Zero D. Less than by excited state
10	Selenium is:	A. An insulator B. A conductor C. Both A and B D. Excellent conductor

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ECAT Pre General Science Physics Chapter 20 MCQ Test With Answer

MCQ's Test For ECAT Pre General Science Physics Chapter 20 Atomic Spectra

ECAT Pre General Science Physics Chapter 20 Atomic Spectra