Physics Mcqs – (Science) MCQs Latest For FPSC, PPSC, NTS, KPPSC, SPSC & Other Tests
“ Physics Mcqs “. Tab this page to check “Latest Physics MCQs” for the preparation of competitive mcqs, FPSC mcqs, PPSC mcqs, SPSC mcqs, KPPSC mcqs, AJKPSC mcqs, BPSC mcqs, NTS mcqs, PTS mcqs, OTS mcqs, Atomic Energy mcqs, Pak Army mcqs, Pak Navy mcqs, CTS mcqs, ETEA mcqs and others. The most occurred mcqs of Physics in past papers. Past papers of Physics mcqs. Past papers of Physics MCQs. Physics Mcqs are the necessary part of any competitive / job related exams. The Physics mcqs having specific numbers in any written test. It is therefore everyone have to learn / remember the related Physics mcqs. The Important series of Physics Mcqs are given below:
In a photoelectric effect monochromatic light is incident on a metal surface. If the incident light of twice the intensity but of same wavelength the kinetic energy of the emitted electron_______________?
A. Becomes half
B. Remains same
C. Becomes double
D. First increases then decrease because of the curvilinear graph
If the wavelength of incident radiation is increased in photoemission then_________________?
A. The minimum kinetic energy of the photoelectrons decreases
B. The maximum kinetic energy of the photoelectrons increases
C. The minimum kinetic energy of the photoelectrons increases
D. The average kinetic energy of the photoelectrons decreases
If a photon is reflected from the mirror then the change in momentum of each photon is_______________?
If n number of the photon is striking on a metal surface then total momentum exerted is_______________?
A photon of wavelength 900nm behaves like a particle of mass______________?
A. 0 kg.
B. 5.53 x 10-36kg
C. 2.46 x 10-36kg
D. 1.84 x 10-44kg
The velocity of a particle of mass m of de-Broglie wavelength λ is______________?
A. v = 2 ×× 10 ms-1
B. v = 3 ×× 106 ms-1
C. v = 2 ×× 6 ms-1
D. v = 2 ×× 106 ms-1
In Davisson-Germer experiment the diffracted proton from crystal shows______________?
A. Light property
B. Wave property
C. Particle property
D. Quantum property
If a diffraction grating is placed in the path of a light beam it reveals______________?
A. Wave property
B. Energy particle
C. Particle property
D. Electromagnetic wave property
In an electron microscope, we use energetic particles because of______________?
A. Kinetic energy is large
B. Penetrating power is high
C. Wavelength is very short
D. All the above reasons
In the electron microscope, electric & magnetic fields are used as_______________?
A. Source of electromagnetic waves
B. Electromagnetic gun
C. Deflecting charged particle
D. Converging source of electrons
A three-dimensional image is obtained by________________?
A. Magnetic imaging
B. Scanning electron microscope
C. Electron microscope
D. None of the above
The uncertainty in momentum & position is due to its_____________?
A. Property of matter and radiation
B. Very high velocity
C. Emission of the certain wavelength
D. Two-dimensional motion
For confinement of electron in a box of radius 10-14m the electron, speed should be_____________?
B. Should be greater than the speed of light.
C. Not be wave-like
D. Be zero
The energy radiated is directly proportional to the fourth power of Kelvins temperature is________________?
A. Rayleigh-Jeans law
B. Karl-Weins law
C. Stephens law
Compton effect proves the________________?
A. Photon theory of light
B. Wave nature of light
C. Dual nature of light
D. Uncertain nature of light
Electron moves in the orbit as________________?
A. Vibratory motion like up and down
B. Standing wave motion
C. Simple vibratory motion
D. S.H.M likes the sound
A lens which converges a beam of parallel rays to a point is called______________?
A. plano concave lens
B. converging (or convex) lens
C. diverging (or concave) lens
D. plano convex lens
The diameter of a lens is called________________?
B. principal axis
C. focal length
D. radius of curvature
Unit of power of a lens is________________?
The power of a concave lens is_______________?
If an object is placed away from 2f of a converging lens then the image will be_______________?
A. virtual and erect
B. real and erect
C. real and inverted
Magnifying power of simple microscope______________?
A. no effect with decrease or increase with focal length
B. increase with decrease in focal length
C. increase with increase in focal length
D. list distance of distinct vision
The least distance of distinct vision for a normal eye is_______________?
A. 30 cm
B. 25 cm
C. 15 cm
D. 40 cm
If a convex lens of large aperture fails to converge the light rays incident on it to a single point, it is said to suffer from______________?
A. chromatic aberration
B. spherical aberration
D. both spherical and chromatic
A convex lens of focal length f1 and a concave lens of focal length f2 are placed in contact. The focal length of the combination is_____________?
A. f2 – f1
B. f2 + f1
In multimode step index fibre the refractive index of core and cladding is____________?
D. different with refractive index of core higher than cladding
Final image produced by a compound microscope is_____________?
A. real and erect
B. real and inverted
C. virtual and erect
D. virtual and inverted
For normal adjustment, length of astronomical telescope is______________?
A. fo + fe
B. fo / fe
C. fo – fe
D. fe / fo
Two convex lenses of equal focal length f are placed in contact the resultant focal length of the combination is______________?
C. 2 f
Least distance of distinct vision_____________?
A. increases with increase in age
B. neither increases nor decreases
C. decreases with increase in age
D. becomes infinite after 60 years
Image of an object 5 mm high is only 1 cm high. Magnification produced by lens is__________________?
A convex lens gives a virtual image only when the objects lies_________________?
A. between principal focus and center of curvature
B. at the principal focus
C. beyond 2 f
D. between principal focus and optical center
The minimum distance between an object and its real image in a convex lens is_____________?
A. 2 f
C. 2.5 f
Dioptre power of an concave lens of 10 cm focal length is_______________?
A. 1 / 10 dioptre
B. 10 dioptre
C. 10 dioptre
D. 1 / 10 dioptre
A point where the incident parallel rays of light converge or appear to diverge after passing through a lens is called______________?
A. optical center
C. center of curvature
The value of critical angle for glass is_______________?
In optic fiber transmission system _____________ are used regenerate the dim light signal?
Magnification of the astronomical telescope is_____________?
Errors in the transmission of power through optic fiber can be minimized by using a______________?
A. Single mode step index fiber
B. Graded index fiber
C. Multimode index fiber
D. Copper wire
The function of collimeter in spectrometer is________________?
A. to produce parallel beams of light
B. to make them
C. to filter the light rays
D. no function
In optic fiber transmission the repeater are separated through a distance of __________ km in newer system?
Michelson devised the formula to calculate the speed of light_______________?
A. C = 8fd
B. C = 4fd
C. C = 16fd
D. C = 5/2fd
A convex lens acts as a diverging lens if the_________________?
A. if the object is with in C
B. object is beyond C
C. if the object is within f
D. both B and C
The equation θ = 1.22 λ/D was devised by_______________?
Michelson calculated the speed of light using the instruments______________?
D. none of these
Ratio of the weight of H-atom to that of an electron is approximately______________?
In hydrogen spectrum which one of the following series lies in the ultraviolet region ?
A. Pfund series
B. Balmer series
C. Bracket series
D. Lymann series
Excited atoms return to their ground state in_______________?
Hydrogen atom does not emit X-rays because _________________?
A. its energy levels are too far apart
B. its energy levels are too close to each other
C. it is too small in size
D. it has a single electron
A. high energy electrons
B. of unknown nature
C. high energy photons
D. radio isotopes
Total number of series in hydrogen spectrum is_____________?
The radiations emitted form hydrogen filled discharge tube show____________?
A. continuous spectrum
B. line spectrum
C. band spectrum
D. absorption spectrum
Photon of highest frequency will be absorbed when transition takes place from_____________?
A. 1st to 5th orbit
B. 3rd to 5th orbit
C. 2nd to 5th orbit
D. 4th to 5th orbit
In obtaining an X-ray photograph of our hand we use the principle of______________?
B. photo electric effect
C. shadow photograph
D. any of above
When we excite some atoms by heat collision or electrical discharge they will________________?
A. emit either invisible or visible light
B. absorb particular wavelengths when white light is incident on them
C. radiate electromagnetic energy of discrete characteristic wavelength
D. radiate electromagnetic energy with a continuous distribution of wavelength
Which one of following postulate is in accordance with the Rutherfords model ?
A. continuous spectra for atoms
B. either continuous nor discrete
C. discrete spectra for atoms
D. no spectrum
Ground state energy of the 4th orbit in a H-atom is_____________?
A. 3.40 eV
B. 13.60 eV
C. 0.85 eV
D. 1.51 eV
The electric P.E of an electron in an orbit at a distance rn from the positive charge_____________?
Bracket series is obtained when all transition of electron terminate on_______________?
A. 4th orbit
B. 3rd orbit
C. 5th orbit
D. 2nd orbit
The penetrating power of X-rays depends on their______________?
C. applied voltage
D. all of the above
Reverse process of photoelectric effect is_______________?
A. Compton effect
B. pair production
C. annihilation of matter
D. X-rays production
Radiation with wavelength longer than red lights______________?
B. ultraviolet rays
C. infra red radiation
D. visible radiation
In an electronic transition atom cannot emit______________?
B. Visible light
C. Infra red radiation
D. Ultraviolet rays
X-rays are similar in nature to_______________?
A. Positive rays
B. Cathode rays
D. Beta rays
When X-rays are passed through successive aluminum sheets what happens to their thickness ?
A. it decreases
C. it remains same
D. sometimes increases and sometimes decreases
Quality of X-rays depends upon ____________ A-filament current B-accelerating voltage C-material of the target ?
A. A & C
B. B & C
C. A & B
D. A B & C
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_______________?
D. impossible to predict
Radiation produced from TV picture tube is_____________?
A. Far infrared
The minimum wavelength of X-rays can further be reduced by _______________?
A. Reducing the pressure or cooling the target
B. Using a target element of higher atomic number
C. Increasing the temperature of the filament.
D. Increasing the potential difference between the cathode and the target
The characteristic X-rays spectrum is due to_____________?
A. The illumination of the target metal by ultra-violet radiation
B. The absorption of radiation by the target metal
C. The bombardment of target by electrons
D. The bombardment of the target by protons
The minimum wavelength of X-rays produced by the bombardment of electrons on the screen of a television set where the accelerating potential is 2.0K V will be______________?
A. 6.2 x 10-10m
B. 3.11 x 10-10m
C. 9.1 x 10-18m
D. 4 x 10-10m
Maximum frequency in the spectrum from X-ray tube is directly proportional to the______________?
A. The soft target which can easily emit electrons
B. The kinetic energy of the incident electron i.e. the potential difference through which they are accelerated
C. Number of incident electron i.e. filament current
D. All of above are correct
X-rays are diffracted by a crystal but not by a diffraction grating because_____________?
A. The lines in a diffraction grating cannot reflect X-rays.
B. The ions in a crystal are well arranged
C. The penetration power of X-rays is high in a diffraction grating
D. The wavelengths of X-rays are of the same order of magnitude as the separation between atoms in a crystal
UV radiation can be produced by______________?
A. Ionization of atoms
B. Electron excitation in the gas
C. Heating the filament
D. All the above
Wave-like characteristic of electron is demonstrated by______________?
A. Production of x-rays.
B. Line spectrum of atoms
C. Diffraction by crystalline solids
D. Photoelectric effect
Electron cannot exist in the nucleus it is confirmed by observing that______________?
A. No antiparticle of electron is present
B. Its size as compare to proton and neutron is very small
C. It does emit radiation
D. The velocity of electron must be very high according to uncertainty principle
In normal state of energy the incident high energy photons will be______________?
A. Cause X-ray emission
D. Cause laser production
In laser production the state in which more atoms are in the upper state than in the lower one is called_____________?
A. Normal state
B. Metal stable state
C. Inverted population
D. All the above
The metastable state for an atom in laser light is_____________?
A. 10-5 sec
B. 10-4 sec
C. 10-3 sec
D. 10-8 sec
In He-Ne laser the lasing action is produced by_______________?
A. Ne only
B. Electrons of He
C. He-Ne both
D. Electrons Ne
Reflecting mirrors in laser is used to______________?
A. Further stimulation
B. For producing more energetic lasers
C. Lasing more
The velocity of laser light is___________________?
A. More than ordinary light
B. Less than ordinary light
C. Equal to ordinary light
D. Different for different colors or frequency
Electrons present in p-type material due to thermal pair generation are_____________?
A. dual carriers
B. minority carriers
C. majority carriers
Semi-conductor germanium and silicon are_________________?
p-n junction when reversed biased acts as a_______________?
C. on switch
D. off switch
In n-p-n transistor, p works as______________?
D. any of above
Identify the correct statement about minority carriers_____________?
A. holes in n-type and free electrons in p-type
B. free electrons in n-type and p-type
C. free electrons in n-type and holes in p-type
D. holes in n-type and p-type
The velocity of an oscillating charge as it moves to and fro along a wire is always_____________?
Which one of the following has the greatest energy gap ?
B. semi conductor
D. any of above
In the transistor schematic symbol, the arrow_______________?
A. is located on the emitter
B. is locate on the collector
C. is located on the base
D. points form north to south
The semiconductor diode can be used as a rectifier because _______________?
A. It has low resistance to the current flow when forward biased & high resistance when reverse biased.
B. It has low resistance to the current flow when forward biased.
C. Its conductivity increases with rise of temperature.
D. It has high resistance to the current flow when reverse biased
The device or circuit used for conversion of A.C. into D.C. is called_______________?
A. Filtering circuit
B. A rectifier
C. An amplifier.
The especially designed semiconductor diodes used as indicator lamps in electronic circuits are___________?
A. The photo diodes
B. The light emitting diode
C. The switch
D. Solar cells.
Semi-conductors with donor atoms and free electrons belong to the type________________?
D. any of above
In p-n-p transistor the collector current is________________?
A. greater than emitter current
B. slightly less than emitter current
C. equal to emitter current
D. any of above
The simplest type of rectification known as half wave rectification is obtained by____________________?
A. suppressing the harmonics in A.C voltage
B. using a transistor
C. suppressing half wave of A.C supply by using diode
D. using a Coolidge tube
Depletion region of a junction is formed_____________?
A. during the manufacturing process
B. under reverse bias
C. under forward bias
D. when temperature varies
Which one of following band is completely filled in case of conductors ?
A. Conduction band
B. Fermi band
C. Forbidden band
D. Valence band
The value of resistivity for insulator is of the order of____________?
A. 106 ohm metre
B. 105 ohm metre
C. 107 ohm metre
D. 108 ohm metre