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

Gaussian surface is always:

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

Question # 3

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 # 4

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

Bohr
A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 5

We can excite an atom by

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

Question # 6

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 # 7

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 # 8

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 # 9

Energy required by an electron revolving in certain orbit to jump to an excited state is called:

Ionization energy A
Ionization potential B
Excitation energy C
Excitation potential D
None of these E

Question # 10

X-ray are also known as

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

Question # 11

The first shell near the neucles is

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

Question # 12

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 # 13

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 # 14

Ultraviolet region lies in ______ series

Layman A
Balmer B
P fund C
B racket D

Question # 15

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 # 16

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 # 17

Graph of Black body radiation is example of

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

Question # 18

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 # 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

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 # 21

CT scanning is the abbreviated name of

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

Question # 22

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 # 23

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 # 24

Braking radiation causes:

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

Question # 25

Static electricity is produced by the transfer of:

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

Question # 26

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 # 27

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 # 28

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 # 29

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 # 30

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

Sr.#	Question	Answer
1	Graph of Black body radiation is example of	A. Band spectra B. Continuo's spectra C. Line spectra D. All
2	Static electricity is produced by the transfer of:	A. Electrons B. Protons C. One fluid D. Two fluid
3	The natural arrangement of colours in the spectrum of white light spectrum is	A. VIBGYOR B. ROYBGIV C. ROYBIGV D. BIGROYV
4	The lasing or active medium in He-Ne laser discharge tube is:	A. Nitrogen B. Helium C. Hydrogen D. Neon
5	The transitions of electrons in the hydrogen atom result in the emission of spectral lies in the:	A. Ultra red region B. Visible region C. Ultraviolet region D. Any of these
6	The value of the metastable state for Neon is	A. 20.66eV B. 20.61eV C. 19.23eV D. 18.70eV
7	The first shell near the neucles is	A. L-shell B. X-shell C. N-shell D. M-shell
8	X-rays can penetrate in a solid matte through a distance of several:	A. Kilo metres B. Metres C. Centimeters D. A few angstroms
9	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
10	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)

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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