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 of the following is an instrument for measuring electric charge or electrical potential difference?
[A] Ammeter
[B] Voltmeter
[C] Electrometer
[D] ohmmeter
Show Answer
Correct Answer: B [Voltmeter]
Notes:
Voltmeter is an instrument for measuring electric charge or electrical potential difference. It was invented by Hans Christian Oersted.
2. How the brain interprets the frequency of an emitted sound is called its __:
[A] Pitch
[B] Amplitude
[C] Intensity
[D] Timbre
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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.
3. Who gave the Theory of Relativity?
[A] Isaac Newton
[B] Archimedes
[C] Albert Einstein
[D] Galileo Galilei
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Correct Answer: C [Albert Einstein]
Notes:
Albert Einstein was the founder of Theory of Relativity. According to Einstein’s theory, mass m is equivalent to energy E given by the relation E = mc^2 where c is speed of light in vacuum. Albert Einstein was awarded the 1921 Nobel Prize in Physics for his contribution to the field of Theoretical Physics.
4. 1 nautical mile is equivalent to which of the following?
[A] 1.44 x 1000 m
[B] 1.852 x 100 m
[C] 1.852 x 1000 m
[D] 1.44 x 100 m
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Correct Answer: C [ 1.852 x 1000 m ]
Notes:nautical mile is a unit of length. 1 nautical mile is equal to 1.852 x 1000 m Other important units of length are:
- 1 mile = 1.609 x 1000 m
- 1 light year = 9.46 x 1015 m
- 1 AU = 1.5 x 1011m
- 1 Par sec = 3.1 x 1016m
5. Newton’s third law of motion applies to which of these forces?
[A] Gravitational
[B] Electric
[C] Magnetic
[D] All of the Above
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Correct Answer: D [All of the Above]
Notes:
Newton’s third law of motion applies to all kinds of forces i.e. Electric, Magnetic, Gravitational etc. It states that every action always has an equal and opposite reaction.
6. What is the product of the mass of the body and its velocity called as?
[A] Force
[B] Linear Momentum
[C] Energy
[D] Power
Show Answer
Correct Answer: B [Linear Momentum]
Notes:
Linear Momentum is the product of the mass of the body and its velocity. Linear Momentum (p) = mass(m) x velocity(v) p= mv Linear momentum is a vector quantity having the direction same as the direction of velocity of the body
7. The work done by a variable force is given by:
[A] area under the force curve and the displacement axis
[B] square of the area under the force curve and the displacement axis
[C] natural log of the area under the force curve and the displacement axis
[D] twice the area under the force curve and the displacement axis
Show Answer
Correct Answer: A [area under the force curve and the displacement axis]
Notes:
The work done by a variable force is given by the area under the force curve and the displacement axis. W = Area ABCDA
8. What is the SI unit of acceleration due to gravity?
[A] ms-2
[B] ms-3
[C] Kgms-2
[D] ms-1
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Correct Answer: A [ms-2]
Notes:
The acceleration due to gravity is the acceleration set up in the body when it falls freely under the effect of gravity alone. The SI unit of acceleration due to gravity is ms-2
9. The value of acceleration due to gravity is minimum on which of these planets?
[A] Mars
[B] Jupiter
[C] Mercury
[D] Neptune
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Correct Answer: C [Mercury]
Notes:
The value of acceleration due to gravity is minimum on planet Mercury and maximum on planet Jupiter.
10. What will happen if a wire of length L is cut into two or more parts?
[A] each part can hold half the weight as full length wire
[B] each part can hold the same weight as full length wire
[C] each part can hold twice the weight as full length wire
[D] None of the above
Show Answer
Correct Answer: B [each part can hold the same weight as full length wire]
Notes:
If a wire of length L is cut into two or more parts, then it’s each part can hold the same weight. Since breaking force is independent of the length of wire.