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

Question # 1

Coulomb multiplied by volt by volt gives the unit called:

farad A
Ohm B
Second C
joule D
Watt E

Question # 2

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 # 3

X-ray are also known as

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

Question # 4

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 # 5

The process of formation of spectrum is called:

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

Question # 6

Static electricity is produced by the transfer of:

Electrons A
Protons B
One fluid C
Two fluid 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

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 # 9

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 # 10

Selenium is:

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

Question # 11

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 # 12

We can excite an atom by

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

Question # 13

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 # 14

The first shell near the neucles is

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

Question # 15

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 # 16

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 # 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

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

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 # 20

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 # 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

Gaussian surface is always:

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

Question # 23

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 # 24

The value of the metastable state for Neon is

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

Question # 25

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 # 26

The inkjet printer eject a thin stream of:

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

Question # 27

Photons must have energy equal to

ev A
En B
hf C
None of these D

Question # 28

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 # 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

Balmer series was identified in:

1685 A
1785 B
1885 C
1985 D
1585 E

Sr.#	Question	Answer
1	The shell closer to the nucleus is called:	A. N shell B. L shell C. K shell D. M shell
2	The results of spectra obtained by Blamer were expressed in 1896 by	A. Bohr B. Rydberg C. Planck D. Rutherford
3	A metastable stae:	A. Is an excited state B. Is that in which excited electron is stable C. Is that in which excited electron is usually unstable D. Means a time interval of 10^-8second
4	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)
5	Static electricity is produced by the transfer of:	A. Electrons B. Protons C. One fluid D. Two fluid
6	The results of spectra obtained by Balmer were expressed in 1896 by:	A. Bohr B. Rydberg C. Planck D. Rutherford
7	The spectrum emitted from hydrogen filled discharge tube is:	A. Line spectrum B. Discrete spectrum C. And spectrum D. Absorption spectrum
8	We can excite an atom by	A. Bombardment of particles B. Radiating photons C. Providing potential difference D. All answer are true
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	The value of the metastable state for Neon is	A. 20.66eV B. 20.61eV C. 19.23eV D. 18.70eV

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ECAT Pre General Science Physics Chapter 20 MCQ Test With Answer

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ECAT Pre General Science Physics Chapter 20 Atomic Spectra