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

Question # 1

The shell closer to the nucleus is called:

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

Question # 2

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 # 3

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 # 4

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 # 5

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 # 6

Selenium is:

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

Question # 7

The electric field lines start from:

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

Question # 8

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 # 9

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 # 10

Photons must have energy equal to

ev A
En B
hf C
None of these D

Question # 11

The first series which was identified in the spectrum of hydrogen is called:

Lyman series A
Balmer series B
Paschen series C
Brackett series D
Pfund series E

Question # 12

The process of formation of spectrum is called:

Interference A
Spectroscopy B
Dispersion C
Reflection D
Botha (A) and (D) E

Question # 13

Braking radiation causes:

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

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

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 # 16

The photocopying process is called:

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

Question # 17

Tick the series which lies in the visible region:

Lyman series A
Balmer series B
Paschen series C
Brackett series D
P fund series E

Question # 18

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 # 19

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

Bohr A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 20

Ultraviolet region lies in ______ series

Layman A
Balmer B
P fund C
B racket D

Question # 21

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 # 22

Balmer series lies in that region of electromagnetic wave spectrum which is called:

Visible region A
Invisible region B
Infra-red region C
ultraviolet region D
None of these E

Question # 23

Static electricity is produced by the transfer of:

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

Question # 24

Gaussian surface is always:

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

Question # 25

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 # 26

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

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

Question # 27

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 # 28

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 # 29

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 # 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	The minimum wavelength of X-rays produced of 1KV potential difference is applied across the anode and cathode of the tube is	A. 1.24 x 10^-10m B. 7.92 x 10^-20m C. 2.78 x 10^-14m D. 3.88 x 10^-11m
2	X-rays can penetrate in a solid matte through a distance of several:	A. Kilo metres B. Metres C. Centimeters D. A few angstroms
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	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	A. Less than atmospheric pressure B. Much less than atmospheric pressure C. Greater than atmospheric pressure D. Much greater than atmospheric pressure
5	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
6	The results of spectra obtained by Blamer were expressed in 1896 by	A. Bohr B. Rydberg C. Planck D. Rutherford
7	The first shell near the neucles is	A. L-shell B. X-shell C. N-shell D. M-shell
8	We can excite an atom by	A. Bombardment of particles B. Radiating photons C. Providing potential difference D. All answer are true
9	An compared to solid matter, a crack or an air bubble allows:	A. Great amount of X-rays to pass B. Smallast amount of X-rays to pass C. Very samall amount of X-rays to pass D. Any of these
10	The range of wavelengths of colurs in the visible colours is	A. 140 nm to 456 nm B. 10 nm to 56 nm C. 410 nm to 656 nm D. 910 nm to 956 nm

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