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 is a source of Atomic Energy ?
[A] Iron
[B] Uranium
[C] Silver
[D] Platinum
Show Answer
Correct Answer: B [Uranium]
Notes:
Uranium is the most common fuel used to produce nuclear energy. Uranium is a nonrenewable energy source that is found in rocks all over the world. However, the specific type of uranium used to produce nuclear energy, called U-235, is rare.
2. Which among the following is true about conduction, convection and radiation mode of transfer of heat?
[A] A Medium is required for conduction but not required for convection and radiation
[B] A medium is required for conduction, convection and radiation
[C] A medium is required for conduction and convection but not required for radiation
[D] A medium is not required for conduction and convectio, radiation
Show Answer
Correct Answer: C [A medium is required for conduction and convection but not required for radiation]
Notes:
A medium is required for conduction and convection but not required for radiation. The radiation can occur even in vaccum but not the others. The conduction can travel through solid. The convection process needs liquid and gas.
3. In which of the following situations the force applied by the weight of a person becomes zero in a lift
[A] Lift moves up with an acceleration of 9.8 meter per sq. second
[B] Lift moves down with an acceleration of 9.8 meter per sq. second
[C] Lift moves up with an speed of 9.8 meter per second
[D] Lift moves up with down speed of 9.8 meter per second
Show Answer
Correct Answer: B [Lift moves down with an acceleration of 9.8 meter per sq. second]
Notes:
The weight of a person becomes zero in a lift. Lift moves down with an acceleration of 9.8 meter per sq. second.
4. Which among the following is the most acceptable range of LEO (Low Earth orbit)?
[A] 350 – 2,600 kms
[B] 200-2000 kms
[C] 160 – 2,000 kms
[D] 160-1600 kms
Show Answer
Correct Answer: C [160 – 2,000 kms]
Notes:
This range is commonly used and accepted in the context of satellite orbits within the Earth’s atmosphere. It extends from approximately 160 kilometers (the Kármán line, which is often used as the boundary of space) to around 2,000 kilometers above the Earth’s surface.
5. A person is standing in front of a wall and makes a sound. What should be the normal minimum distance between the person and the wall , so that the person hears echo?
[A] 6 meters
[B] 13 meters
[C] 20 meters
[D] 17 meters
Show Answer
Correct Answer: D [17 meters]
Notes:
To hear an echo, the minimum distance between a wall and the source of sound is 17m. The minimum interval is 0.1 sec.
6. Which among the following is the SI physical unit of dynamic viscosity?
[A] Poise
[B] Pascal-second
[C] Newton-second
[D] Poise-second
Show Answer
Correct Answer: B [Pascal-second]
Notes:
The SI unit for dynamic viscosity η is the Pascal-second (Pa-s). It corresponds to the force (N) per unit area (m2) divided by the rate of shear (s-1).
7. How the brain interprets the frequency of an emitted sound is called its __:
[A] Pitch
[B] Amplitude
[C] Intensity
[D] Timbre
Show Answer
Correct Answer: A [ Pitch]
Notes:
How the brain interprets the frequency of an emitted sound is called the pitch. Researchers have discovered a discrete region of the monkey brain that processes pitch, the relative high and low points of sound, by recognizing a single musical note played by different instruments.
8. Which among the following is the correct sequence of the terms used for various phases of the rocky object from space entering earth’s atmosphere and reaching on earth?
[A] Meteoroid – Meteor – Meteorite
[B] Meteorite – Meteoroid – Meteor
[C] Meteor – Meteorite – Meteoroid
[D] Meteoroid – Meteorite – Meteor
Show Answer
Correct Answer: A [ Meteoroid – Meteor – Meteorite]
Notes:
A meteoroid is a small rocky or metallic body travelling through space. When such an object enters the Earth’s atmosphere, it heats up from atmospheric friction and produces a streak of light, both from the glowing object and the trail of glowing particles that it leaves in its wake. This phenomenon is called a meteor, or colloquially a “shooting star” or “falling star”. If a meteoroid, comet or asteroid or a piece thereof withstands ablation from its atmospheric entry and impacts with the ground, then it is called a meteorite. (Wikipedia)
9. 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.
10. Which of these branches of Physics deal with heat and temperature and their relation to energy and work?
[A] Geophysics
[B] Mechanics
[C] Atomic Physics
[D] Thermodynamics
Show Answer
Correct Answer: D [Thermodynamics]
Notes:
Thermodynamics is that branch of physics which deals with heat and temperature and their relation to energy (such as mechanical, electrical, or chemical energy) and work. The behaviour of these quantities is governed by the four laws of thermodynamics
