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

Question # 1

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 # 2

The electric field lines start from:

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

Question # 3

The inkjet printer eject a thin stream of:

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

Question # 4

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 # 5

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 # 6

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 # 7

Selenium is:

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

Question # 8

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 # 9

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 # 10

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 # 11

The value of the metastable state for Neon is

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

Question # 12

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 # 13

Photons must have energy equal to

ev A
En B
hf C
None of these D

Question # 14

Balmer series was identified in:

1685 A
1785 B
1885 C
1985 D
1585 E

Question # 15

Graph of Black body radiation is example of

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

Question # 16

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 # 17

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 # 18

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 # 19

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 # 20

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

Bohr
A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 21

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

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

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

Bohr A
Rydberg B
Planck C
Rutherford D
Coulomb E

Question # 24

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 # 25

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 # 26

We can excite an atom by

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

Question # 27

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 # 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

CT scanning is the abbreviated name of

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

Question # 30

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

Sr.#	Question	Answer
1	The process of formation of spectrum is called:	A. Interference B. Spectroscopy C. Dispersion D. Reflection
2	The He-Ne laser discharge tube is filled with:	A. 85% He B. 15% He C. 50% He D. 60% He
3	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
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	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)
6	CT scanning is the abbreviated name of	A. Computed Technology B. Computed Technique C. Computed Technology D. Computerized Technique
7	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
8	The natural arrangement of colours in the spectrum of white light spectrum is	A. VIBGYOR B. ROYBGIV C. ROYBIGV D. BIGROYV
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	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

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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