Home/ECAT/ECAT Physics Atomic Spectra Test Online

ECAT Physics Atomic Spectra Test Online

Danial MalikLast Updated: April 18, 2025

Physics Atomic Spectra Online Test

ECAT Physics Atomic Spectra Chapter Online Test

Total Questions:	70
Time Allowed:	30 Minutes
Total Marks:	70
How to Attempt Test:	Please choose the right Option in MCQ-type question.
Test Helpful For:	ECAT Entry Test Physics Online Test Interview Questions about Physics All Universities Entrance Test Recruitments Tests

Page 1 of 3

1. Brackett series of hydrogen atom spectrum lies in

Far infra-red region

Ultraviolet region

Visible region

Infra-red region

2. Hydrogen atom spectrum consist of lines I

Ultraviolet

Infra-red

Visible

All of these

3. Spectral gives are emitted from hydrogen atoms when electrons

Absorb energy

Radiate energy due to the change of their orbital motion

Emit energy while jumping down to a lower energy level

Radiate energy due to their orbital motion

4. Ionization of hydrogen atom originally in its ground level takes a minimum amount of energy equal to

2.4 Joules

4, 1856 ergs

12,398 eq

13.3ev

5. An example of an absorption spectrum in the spectrum of

A mercury vapour lamp

Atomic hydrogen

Sodium vapour

The sun

6. Excited atoms return to their ground state in

10¯¹⁰ s

10¯⁸ s

10¯⁶ s

10¯⁹ s

7. Hydrogen atom does not emit X-rays because

Its energy levels are too close to each other

Its energy levels are too far apart

It is too small in size

It has a single electron

8. Total number of series in hydrogen spectrum is

Three

Four

Five

Six

9. Bracket series is obtained when all transition of electron terminate on

4th orbit

5th orbit

3rd orbit

2nd orbit

10. The two spectral series, which deal with the transitions for far-infra-red. Region is

Balmer and Paschen Series

Lyman and P fund Series

Bracket and P fund Series

Lyman and, Balmer, Series

11. The numerical value of ground state energy for the hydrogen atom is

E₁ = 13.6 ev

E₁ = — 5.6 ev

E₁ = — 10. 6ev

E₁ = — 13.6ev

12. The radius of the third Bohr orbit in hydrogen atom is greater than the radius of the first orbit by a factor of

13. Energy required by an atom to move from ground state to higher energy sate is called

Excitation energy

Ionization energy

Ionization potential

None of these

14. When electro absorbs Energy it jumps to

Ground level

Infinity

Lower energy level

Higher energy level

15. Total energy of an electron in an orbit around the nucleus. Is the sum of

Rotational energy & vibrational energy

Vibrational energy & kinetic energy

Rotational energy & kinetic energy

None of these

16. Ground sate energy of the 4th orbit in a H-atom is

-13.60 eV

-3.40 eV

-0.85 eV

-1.51 eV

17. The penetrating power of X-rays depends on their

Applied voltage

Frequency

Source

All of these

18. When X-rays are passed through successive aluminum sheets what happens to their thickness?

Increases

It decreases

It remains same

Sometime increases and sometimes decreases

19. In an X-ray tube electrons each of charge e are accelerated through V potential difference allowed to hit a metal target. The wavelength of the X-rays emitted is

he/ev

he/Vc

eV/h

impossible to predict

20. The minimum wavelength of X-rays can further be reduced by

Reducing the pressure or cooling the target

Increasing the temperature of the filament

Using a target element of higher atomic number

Increasing the potential difference between the cathode and the target.

21. The characteristic X-rays spectrum is due to

The illumination of the target metal by ultra-violet radiation

The bombardment of the target by protons

The bombardment of target by electrons

The absorption of ? radiation by the target metal

22. Maximum frequency in the spectrum from X-ray tube is directly proportional to the

Number of incident electron i.e. filament current

The kinetic energy of the incident electron i.e. the potential difference through which they are accelerated

The soft target which can easily emit electrons

All of these

23. X-rays are diffracted by a crystal but not by a diffraction grating because

The ions in a crystal are well arranged

The lines in a diffraction grating cannot reflect X-rays

The penetration power of X-rays is high in a diffraction grating

The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal

24. When an electron in hydrogen atom jumps from higher orbit into third orbit. The set of lines emitted is called

Balmer series

Lyman series

Bracket series

Paschen series

25. Spectroscopy is the branch of physics deals with the electromagnetic radiation emitted and absorbed by

Atoms

Molecules

Both

None of these

Page 2 of 3

26. Paschen series lies in which region?

Visible region

Ultra violet region

Infra red region

Far-infra red region

27. Different elements can be identified by spectroscopy on the basis of

Intensity

Wavelength

Range

None of these

28. Using spectroscopy the helium was identified in the environment of

Moon

Sun

Earth

None of these

29. The transitions of inner-shell electrons in heavy atoms give

α – rays

β – rays

ϒ – rays

X – rays

30. The quantized energy of first Bohr orbit of hydrogen atom is

13.04 eV

-13.6 eV

13.6 eV

13.5 eV

31. Bremsstrahlung are those in which radiations lie in

Long wavelength region

Short wavelength region

Wavelength in X-ray region

None of these

32. An interesting application of laser is the production of three dimensional images called

Polygons

Holograms

Ovals

None of these

33. The radius of a typical nucleus is less than

10¯¹⁰ m

10¯¹¹ m

10¯¹² m

10¯¹⁴ m

34. A discharge tube of He – Ne laser, is filled with helium by

80 %

85 %

90 %

None of these

35. The radius of second orbit of Hydrogen atom is

0.53 A⁰

2.12 A⁰

3.53 A⁰

4.12 A⁰

36. Which are the fundamental particles of an atom?

Electron, Proton, Neutron

Electron, Proton, Helium Nucleus

Electron, Neutron, Positron

Proton, Neutron, Positron

37. The nucleus of hydrogen ₁H³ is called

Proton

Deuteron

Tritium

All of these

38. Elements with atomic number Z > 82 are

Stable

Unstable

Small

None of these

39. In Bremsstrahlung the rate of slowing down of electrons is

Small

Unpredictable

Very large

None of these

40. A crack or air bubble in a metal sheet allows X-rays to pass in

Small amount

Very small amount

Greater amount

None of these

41. Which of the following particles can induce artificial radio-activity easily in certain nuclei?

α – particle

β – particle

ϒ – particle

All of these

42. How much energy is released by fission of one uranium nucleus?

211.5 Mev

831.5 Mev

711.5 Mev

631.5 Mev

43. The inner shell transition is the phenomenon in which the electrons are emitted from

Light metals

Light non-metals

Heavy metals

Heavy non-metals

44. Laser bean can be used for

Wilding of detached retinas

Destroy tissues in a localized area

Scaled off capillaries for prevention of disease

All of these

45. Laser beam can be used to generate

One dimensional images

Two dimensional images

Three dimensional images

Four dimensional images

46. Which of the following pair has nearly identical metastable states?

Hydrogen, Chlorine

Helium, Neon

Helium, Calcium

None of these

47. A finely focused beam of laser is used to destroy

Cancerous cells

Somatic cells

Large cells

Infected calls

48. Hydrogen bomb is based on the principle of

Nuclear Fission

Nuclear Fusion

Nuclear Chain Reaction

None of these

49. Which of the following is not a radioactive element?

Polonium

Radium

Uranium

Hydrogen

50. Which of the following particles has very high ionization capability?

α – particle

β – particle

ϒ – particle

All of these

Page 3 of 3

51. The number of neutrons ‘N’ is equal to

N = A – Z

N = A + Z

N = A x Z

N = ½ A + Z

52. Pauli’s exclusion principle states that no two atomic electrons can:

Be in the same orbital

Be in the same shell

Have same values of all the quantum numbers

Have same angular momentum

53. Pauli’s exclusion principle is also called

Equivalence principle

Correspondence principle

Uncertainty principle

None of these

54. The angular momentum of the orbital electron is integral multiple of:

2πh

h/2π

None of these

55. Bohr’s atomic model gained acceptance above all other models because it:

Is based on quantum hypothesis

Explained the constitution of atom

Assumed continuous radiation of energy by orbiting electrons

Explained hydrogen spectrum

56. Rutherford’s experiments on scattering of α-particles proved that:

Atom is mostly empty

Positive charge is uniformly distributed in the atom

Number of positive charges in equal to the number of negative charges

Atoms contain electrons

57. Who proposed that the orbits of the electron in the atom are elliptical?

Thomson

Bohr

Rutherford

Summer field

58. There are discrete energy levels in atoms. It was first experimentally demonstrated by

Rutherford’s experiment

Franck Hertz experiment

Bohr’s experiment

Summerfield experiment

59. Which of the following sources give discrete emission spectrum?

Incandescent electric bulb

Sun

Mercury vapour lamp

Candle

60. Band spectrum is produced by

H₂

61. The nuclear model of atom was proposed by

J.J. Thomson

E. Rutherford

Nell Bohr

Summerfield

62. In which region of electromagnetic spectrum does the Lyman series of hydrogen atom lie

Ultraviolet

Infra red

Visible

X-ray

63. According to classical theory the proposed circular path of an electron in Rutherford model of atom will be

Circular

Straight line

Parabolic

Spiral

64. According to Classical theory, the Rutherford model of atom is

Stable

Unstable

Semi-stable

Meta-stable

65. The angular momentum of electron in nth orbit in given by

h/2πn

n h/2π

n² h/2π

66. When a hydrogen atom is raised from the ground state to an excited state

P.E. increases and K.E. decreases

P.E. decreases and K.E. increases

Both kinetic energy (K.E) and potential energy (P.E) increases

Both K.E. and P.E. decreases

67. How does the energy difference between the consecutive energy level very as the quantum number ‘n’ increases?

Increases

Decreases

Remains unchanged

First increases and then decreases

68. Which of the following is the property of Rydberg constant?

It is universal constant

It is same for all the hydrogen like atoms

It depends on the atomic number of the atom

It depends on the mass number of the atom

69. Which source is associated with a line emission spectrum?

Electric fire

None street sign

Red traffic light

Sun

70. If we consider electrons and photons of the same wavelength, then they will have the same

Velocity

Angular momentum

Energy

Momentum

You Can Learn and Gain more Knowledge through our Online Quiz and Testing system Just Search your desired Preparation subject at Gotest.

ECAT Chemistry Environmental Chemistry Test Online
ECAT Chemistry Common Chemical Industries in Pakistan Test O...
ECAT Chemistry Macro-Molecules Test Online
ECAT Chemistry Carboxylic Acid Test Online
ECAT Chemistry Aldehydes and Ketones Test Online
ECAT Chemistry Alcohols Phenols And Ethers Test Online
ECAT Chemistry Alkyl Halides Test Online
ECAT Chemistry Aromatic Hydrocarbons Test Online
ECAT Chemistry Aliphatic Hydrocarbons Test Online
ECAT Chemistry Fundamental Principles of Organic Chemistry T...

Danial MalikLast Updated: April 18, 2025

Facebook Twitter Reddit WhatsApp Share via Email Print

ECAT Physics Atomic Spectra Test Online

Physics Atomic Spectra Online Test

ECAT Physics Atomic Spectra Chapter Online Test

You Might Also Like

Danial Malik

Leave a Reply Cancel reply

Physics Atomic Spectra Online Test

ECAT Physics Atomic Spectra Chapter Online Test

You Might Also Like

Danial Malik

Your Related

ECAT Mathematics Introduction to Analytic Geometry Online Test

PU Lahore Entry Test 2025 Registration Forms Schedule Time Test Centers

UET Lahore Combined Entrance Test 2025 – Apply Online

ECAT Chemistry Carboxylic Acid Test Online

NED-Karachi ECAT Chemistry Entry Test Online Preparation

ECAT Physics Of Solids Online Test

Leave a Reply Cancel reply