Physics Objective (Multiple Choice) General Knowledge & General Science Questions & Answers for SSC-CGL, UPPSC, NDA, CDS and all one day examinations of India. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
1. When a tubelight breaks, a cracking sound is produced because ____?
[A] Pressure inside the lamp is less than atmospheric pressure
[B] Pressure inside the lamp is more than atmospheric pressure
[C] The lamp is filled with reactive gases
[D] The lamp is filled with mercury vapour
Show Answer
Correct Answer: A [Pressure inside the lamp is less than atmospheric pressure ]
Notes:
A fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and argon, xenon, neon, or krypton. The pressure inside the lamp is around 0.3% of atmospheric pressure.
2. Newton-meters per second is represented as follows?
[A] Ohm
[B] Volt
[C] Watt
[D] Calorie
Show Answer
Correct Answer: C [Watt]
Notes:
one watt is the rate at which work is done when an object is moved at a speed of one meter per second against a force of one Newton.
3. Which among the following is measured by an Odometer?
[A] Pressure
[B] Height
[C] Distance
[D] Velocity
Show Answer
Correct Answer: C [Distance]
Notes:
An odometer is an instrument used for measuring the distance. It measures distance traveled by a vehicle such as a bicycle or car. The device may be electronic, mechanical, or a combination of the two.
4. If a Candle is make to burn in Zero Gravity__:
[A] The Candle will burn for a very long time compared to normal gravity
[B] The flame of the candle will become round
[C] There is no impact of gravity on the burning of candle
[D] The Candle will not burn in zero gravity
Show Answer
Correct Answer: B [ The flame of the candle will become round]
Notes:
Gravity plays a role in flame formation. Modifying the gravity causes different flame types. The common distribution of a flame under normal gravity conditions depends on convection, as soot tends to rise to the top of a general flame, as in a candle in normal gravity conditions, making it yellow. In micro gravity or zero gravity, such as an environment in outer space, convection no longer occurs, and the flame becomes spherical, with a tendency to become more blue and more efficient (although it may go out if not moved steadily, as the CO2 from combustion does not disperse as readily in micro gravity, and tends to smother the flame).
5. The frequency range of Ultra High Frequency (UHF) is __?
[A] 3 to 10 Megahertz
[B] 3 to 30 Megahertz
[C] 300 to 3000 Megahertz
[D] 300 to 30000 Megahertz
Show Answer
Correct Answer: C [ 300 to 3000 Megahertz]
Notes:
Ultra High Frequency (UHF) designates the ITU radio frequency range of electromagnetic waves between 300 Megahertz to 3 GHz (3,000 Megahertz).
6. Which of the following is the unit of Solid Angle?
[A] radian
[B] steradian
[C] m2
[D] π
Show Answer
Correct Answer: B [ steradian ]
Notes:
Steradian is the unit of Solid Angle (Angle in Space). One steradian is defined as the solid angle of a sphere subtended at the centre of a sphere by that surface of the surface whose area is equal to the square of the sphere’s radius. Its symbol is sr.
7. What is the relation between velocity and acceleration at the highest point of projectile path?
[A] both are at an angle of 45° to each other
[B] both are perpendicular to each other
[C] both are at an angle of 180° to each other
[D] None of the above
Show Answer
Correct Answer: B [both are perpendicular to each other]
Notes:
At the highest point of projectile path, the velocity and acceleration are perpendicular to each other. At the highest point of projectile path, the projectile possesses velocity only along the horizontal direction.
8. Which of the following is NOT correct about Vectors addition?
[A] Vectors addition is associative
[B] Vectors addition is commutative
[C] Vectors of different natures can be added
[D] None of the above
Show Answer
Correct Answer: C [Vectors of different natures can be added]
Notes:
Vectors addition is associative and commutative. But vectors of the same nature alone can be added. Example: a Force vector cannot be added to velocity vector as they are of different nature.
9. Which of the following statements is correct?
[A] The acceleration due to gravity is same at the equator and the poles
[B] The acceleration due to gravity is maximum at the poles
[C] The acceleration due to gravity is least at the poles
[D] None of the above
Show Answer
Correct Answer: B [The acceleration due to gravity is maximum at the poles]
Notes:
The acceleration due to gravity is maximum at the poles and is least at the equator. The value of acceleration due to gravity increases as we go from the equator to the pole.
10. The value of acceleration due to gravity is minimum on which of these planets?
[A] Mars
[B] Jupiter
[C] Mercury
[D] Neptune
Show Answer
Correct Answer: C [Mercury]
Notes:
The value of acceleration due to gravity is minimum on planet Mercury and maximum on planet Jupiter.
