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 has highest velocity ?
[A] Hurricane
[B] Tornado
[C] Typhoon
[D] Cyclone
Show Answer
Correct Answer: B [Tornado]
Notes:
Tornadoes has the highest velocity and are more devastating compared to other types of cyclones. They generally occur in the pacific ocean.
2. 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.
3. At which of the following places water shall boil at the lowest temperature?
[A] Kochi
[B] Ooty
[C] Mount Abu
[D] New Delhi
Show Answer
Correct Answer: B [Ooty]
Notes:
This question is related to Antoine equation. Water to get boil, its vapour pressure must reach to its surrounding pressure. In a pressure cooker, it boils at the highest temperature. Elevation of Kochi is 0 m, ooty is 2,486 m, Mount Abu is 1,200 m, New Delhi is 216 m, Shimla is 2,205 m. So comparing all of them, water will boil at lowest temperature at ooty, followed by Shimla, Mount Abu , New Delhi and Kochi. This is because , higher we go lower is the atmospheric pressure and lower is the point where water`s vapour pressure gets equal to the atmospheric pressure.
4. Crystals of which of the following naturally-occuring substance exhibits both ‘pyroelectric’ and ‘piezoelectric’ properties making it versatile for application in the field of electronics?
[A] Quartz
[B] Mica
[C] Topaz
[D] grapite
Show Answer
Correct Answer: A [Quartz]
Notes:
Quartz crystals have piezoelectric properties: they develop an electric potential upon the application of mechanical stress. An early use of this property of quartz crystals was in phonograph pickups. A common piezoelectric use of quartz today is as a crystal oscillator. The quartz clock is a familiar device using the mineral. Quartz is also strongly pyroelectric. Temperature changes create positive and negative charges within the crystal.
5. With reference to the nuclear energy, what is the Special Nuclear Material (SNM)?
[A] A nuclear material that is NOT capable of sustaining a chain reaction of nuclear fission
[B] A fissile material that is capable of sustaining a chain reaction of nuclear fission
[C] A fissile material that is NOT capable of sustaining a chain reaction of nuclear fusion
[D] A fissile material that is capable of sustaining a chain reaction of nuclear fusion
Show Answer
Correct Answer: B [ A fissile material that is capable of sustaining a chain reaction of nuclear fission]
Notes:
A nuclear fissile material that is capable of sustaining a nuclear reaction is called Special Nuclear Material.
6. 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)
7. Which of the following is correct about the properties of Gravitational Forces?
[A] They are the strongest forces in nature
[B] They observe inverse square law
[C] Both a and b
[D] None
Show Answer
Correct Answer: B [They observe inverse square law]
Notes:
Gravitational Forces are the weakest forces in nature. They obey inverse square law as they vary inversely as the square of the distance between the two bodies. They are central forces and conservative forces. They operate over very long distances having an infinite range.
8. 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
Show Answer
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
9. What is represented by the slope of a straight line joining two points on a velocity-time graph?
[A] Average velocity
[B] Instantaneous acceleration
[C] Average acceleration
[D] None of the above
Show Answer
Correct Answer: C [Average acceleration]
Notes:
The slope of a straight line joining two points on a velocity-time graph gives the average acceleration between these two points. Depending on the sign of slope, the average acceleration can be positive or negative.
10. Two vectors are said to be equal if:
[A] they have equal magnitude and same direction
[B] they have equal magnitude and opposite direction
[C] they have equal magnitude and common initial point
[D] they have equal magnitude irrespective of the direction
Show Answer
Correct Answer: A [they have equal magnitude and same direction]
Notes:
Two vectors are said to be equal if they have equal magnitude and same direction. Two vectors are said to be co-initial if their initial point is common.
