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 first shell near the neucles is

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

Question # 3

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

Bohr A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 4

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 # 5

Ultraviolet region lies in ______ series

Layman A
Balmer B
P fund C
B racket D

Question # 6

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 # 7

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 # 8

The minimum wavelength of X-rays produced of 1KV potential difference is applied across the anode and cathode of the tube is

1.24 x 10^-10m A
7.92 x 10^-20m B
2.78 x 10^-14m C
3.88 x 10^-11m D

Question # 9

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 # 10

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 # 11

We can excite an atom by

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

Question # 12

The formula of Brackett series can be obtained by putting in the general formula, the value of n equal to:

one
A
two B
three C
four D
five E

Question # 13

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 # 14

The inkjet printer eject a thin stream of:

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

Question # 15

X-ray are also known as

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

Question # 16

The electric field lines start from:

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

Question # 17

Gaussian surface is always:

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

Question # 18

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 # 19

The photocopying process is called:

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

Question # 20

Selenium is:

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

Question # 21

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 # 22

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 # 23

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 # 24

Static electricity is produced by the transfer of:

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

Question # 25

Braking radiation causes:

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

Question # 26

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 # 27

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 # 28

CT scanning is the abbreviated name of

Computed Technology A
Computed Technique B
Computed Technology C
Computerized Technique D

Question # 29

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 # 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	Energy required by an electron revolving in certain orbit to jump to an excited state is called:	A. Ionization energy B. Ionization potential C. Excitation energy D. Excitation potential
2	CT scanning is the abbreviated name of	A. Computed Technology B. Computed Technique C. Computed Technology D. Computerized Technique
3	Tick the series which lie/s in. the infra-red region.	A. Pfund series B. Brackett series C. Paschen series D. All of these
4	The He-Ne laser discharge tube is filled with:	A. 85% He B. 15% He C. 50% He D. 60% He
5	The shell closer to the nucleus is called:	A. N shell B. L shell C. K shell D. M shell
6	Ultraviolet region lies in ______ series	A. Layman B. Balmer C. P fund D. B racket
7	If the distance between two charges is doubled,the force between them will become:	A. Double B. Half C. One third D. One fourth
8	Braking radiation causes:	A. Continuous spectrum B. Line Spectrum C. Band spectrum D. Discrete specturm
9	X-ray are also known as	A. Roentgen rays B. Maxwell rays C. Plank range D. Einstein rays
10	Graph of Black body radiation is example of	A. Band spectra B. Continuo's spectra C. Line spectra D. All

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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