Physics MCQs
Physics Objective (Multiple Choice) General Knowledge & General Science Questions & Answers for SSC-CGL, UPPSC, NDA, CDS and all one day examinations of India.
1. Which among the following kinds of lenses are used to treat Astigmatism?
[A] Convex Lens
[B] Concave Lens
[C] Bifocal Lens
[D] Cylindrical
Show Answer
Correct Answer: D [Cylindrical]
Notes:
Astigmatism is due to imperfect spherical nature of eye lens. The focal length of eye lens is in two orthogonal directions become different so they cannot see objects in two orthogonal directions simultaneously. This defect in direction can be removed by using cylindrical lens in a particular direction.
2. Which among the following would be most commonly affected, if the filament of a electric Bulb is not uniform?
[A] Light
[B] Life
[C] Resistance
[D] None of the above
Show Answer
Correct Answer: B [Life]
Notes:
If the filament of the bulb is affected then the life of the bulb is affected. Filament is very important for the bulb to function.
3. Which among the following principle is used by Bats?
[A] RADAR (Radio Detective & Ranging
[B] SONAR (Sound Navigation & Ranging
[C] law of reflection
[D] law of diffraction
Show Answer
Correct Answer: B [SONAR (Sound Navigation & Ranging]
Notes:
Bats use SONAR (Sound Navigation & Ranging).Sonar is a technique that uses sound propagation to navigate, communicate with or detect objects on or under the surface of the water, such as other vessels.
4. On which of the following Inertia of an object depends ?
[A] Bulk
[B] Size
[C] Shape
[D] Mass
Show Answer
Correct Answer: D [Mass]
Notes:
Inertia is the resistance experienced by an object to any change in its velocity. This includes changes to the object’s speed, or direction of motion. Inertia of rest, Inertia of motion are the examples.
5. While passing over an obstacle a light ray slightly bends round the corner. The phenomenon is known as__:
[A] Scattering
[B] Polarisation
[C] Diffraction
[D] Refraction
Show Answer
Correct Answer: C [ Diffraction]
Notes:
The phenomenon of light rays bending around the corners of obstacles is called diffraction. Diffraction refers to various phenomena that occur when a wave encounters an obstacle or a slit.
6. Which among the following Radio frequencies are used around the world in air navigational system?
[A] Very Low Frequency (VLF)
[B] Very High Frequency (VHF)
[C] Tetrahertz Radiation (THF)
[D] Ultra High Frequency (UHF)
Show Answer
Correct Answer: B [ Very High Frequency (VHF)]
Notes:
VHF (Very High Frequency) omnidirectional radio range (VOR), is a short-range radio navigation system for aircraft, enabling aircraft to determine their position and stay on course by receiving radio signals transmitted by a network of fixed ground radio beacons, with a receiver unit. Uses radio frequencies in the very high frequency (VHF) band from 108 to 117.95 MHz. VOR is the standard air navigational system in the world, used by both commercial and general aviation.
7. Large Underground Xenon experiment (LUX) is being carried out in which country?
[A] U.S.A
[B] Russia
[C] China
[D] Japan
Show Answer
Correct Answer: A [ U.S.A]
Notes:
Large Underground Xenon experiment (LUX) is located 1,510 m underground at the Sanford Underground Laboratory in Lead city, South Dakota, United States.
8. Who among the following gave the Uncertainity principle?
[A] R.A Milkman
[B] Ernset Rutherford
[C] S.N Bose
[D] Werner Heisenberg
Show Answer
Correct Answer: D [Werner Heisenberg]
Notes:
Werner Heisenberg, a german Physicist, discovered the Uncertainity principle. As per the uncertainty principle, we cannot measure the position (x) and the momentum (p) of a particle with absolute precision. The more accurately we know one of these values, the less accurately we know the other. It represnts the effects of wave-particle duality on the properties of subatomic objects.
9. Which of the following is NOT a unit for measuring pressure?
[A] bar
[B] torr
[C] Pascal
[D] shake
Show Answer
Correct Answer: D [ shake ]
Notes:
bar, torr and Pascal are the units used for measuring pressure whereas shake is a unit of time. 1 bar = 105 Pa 1 bar = 760 torr 1 bar = 1 atmospheric pressure Shake is the smallest practical unit of time. 1 shake = 10-8s
10. The magnitude of the resultant of two vectors is maximum in which of the following case?
[A] when vectors act in the same direction
[B] when vectors act in the opposite direction
[C] when vectors act at 90° to each other
[D] None of the above
Show Answer
Correct Answer: A [when vectors act in the same direction]
Notes:
The magnitude of the resultant of two vectors is maximum when vectors act in the same direction. The magnitude of the resultant of two vectors is minimum when vectors act in the opposite directions.