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

Question # 1

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 # 2

We can excite an atom by

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

Question # 3

The results of spectra obtained by Balmer were expressed in 1896 by:

Bohr
A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 4

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 # 5

Static electricity is produced by the transfer of:

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

Question # 6

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 # 7

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

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

Question # 8

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 # 9

Coulomb multiplied by volt by volt gives the unit called:

farad A
Ohm B
Second C
joule D
Watt E

Question # 10

The natural arrangement of colours in the spectrum of white light spectrum is

VIBGYOR A
ROYBGIV B
ROYBIGV C
BIGROYV D
None of these E

Question # 11

The spectrum emitted from hydrogen filled discharge tube is:

Line spectrum A
Discrete spectrum B
And spectrum C
Absorption spectrum D
Both (A) and (B) E

Question # 12

Graph of Black body radiation is example of

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

Question # 13

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 # 14

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 # 15

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 # 16

The value of the metastable state for Neon is

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

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

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 # 19

The electric field lines start from:

Positive charge A
Negative charge B
Either A and B C
Neutron D
An atom E

Question # 20

The first shell near the neucles is

L-shell A
X-shell B
N-shell C
M-shell D

Question # 21

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

Bohr A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 22

The shell closer to the nucleus is called:

N shell A
L shell
B
K shell C
M shell D
O shell E

Question # 23

In helium Neon Laser Neon = 15% and Helium = 85% used. The lasing gas this unit is

Helium A
Neon B
Both C
None of these D

Question # 24

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 # 25

X-rays produced in a tube operating at 10⁵V. The speed of X-rays produced is

3 x 10⁸m/s A
3.1 x 10⁸m/s B
2.8 x 10⁸m/s C
1.88 x 10⁸m/s D

Question # 26

Braking radiation causes:

Continuous spectrum A
Line Spectrum B
Band spectrum C
Discrete specturm D
All of these E

Question # 27

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 # 28

The range of wavelengths of colurs in the visible colours is

140 nm to 456 nm A
10 nm to 56 nm B
410 nm to 656 nm C
910 nm to 956 nm D
None of these E

Question # 29

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 # 30

The inkjet printer eject a thin stream of:

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

Sr.#	Question	Answer
1	Selenium is:	A. An insulator B. A conductor C. Both A and B D. Excellent conductor
2	Spectrum represents the number of component colours present in certain light in terms of:	A. Wavelength B. Frequency C. Energy D. Both (A) and (B)
3	X-rays produced in a tube operating at 10⁵V. The speed of X-rays produced is	A. 3 x 10⁸m/s B. 3.1 x 10⁸m/s C. 2.8 x 10⁸m/s D. 1.88 x 10⁸m/s
4	In helium Neon Laser Neon = 15% and Helium = 85% used. The lasing gas this unit is	A. Helium B. Neon C. Both D. None of these
5	The inkjet printer eject a thin stream of:	A. Water B. Oil C. Ink D. Any above
6	In case of braking radiations, when the rate of deceleration is very large, the emitted radiation corresponds to:	A. Short wavelength B. Large wavelength C. Very large wavelenth D. Low frequency
7	X-rays can penetrate in a solid matte through a distance of several:	A. Kilo metres B. Metres C. Centimeters D. A few angstroms
8	We can excite an atom by	A. Bombardment of particles B. Radiating photons C. Providing potential difference D. All answer are true
9	The electric field lines start from:	A. Positive charge B. Negative charge C. Either A and B D. Neutron
10	Balmer series was identified in:	A. 1685 B. 1785 C. 1885 D. 1985

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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