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 true regarding Sound Waves?
[A] They are longitudinal waves and material medium is not required for their propagation
[B] They are transverse waves and material medium is required for their propagation
[C] They are longitudinal waves and material medium is required for their propagation
[D] They are transverse waves and material medium is not required for their propagation
Show Answer
Correct Answer: C [They are longitudinal waves and material medium is required for their propagation]
Notes:
The sound waves are longitudinal waves and material medium is not required for their propagation. The sound waves can travel through solid, liquid and gas.
2. 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.
3. Which of the following waves can be used to measure the speed of a approaching car?
[A] Light waves
[B] Micro waves
[C] Radio waves
[D] Sound waves
Show Answer
Correct Answer: C [Radio waves]
Notes:
Radio waves are a type of electromagnetic radiation with wavelengths in the electromagnetic spectrum longer than infrared light. Radio waves have frequencies as high as 300 gigahertz to as low as 30 hertz. It is used to measure the speed of an approaching car.
4. “Svedberg Unit” is a measure of?
[A] Concentration
[B] Size
[C] Density
[D] Time
Show Answer
Correct Answer: D [Time]
Notes:
A Svedberg unit (S/ Sv) is utilized to denote sedimentation coefficients, providing specific measurement of a particle based on its sedimentation rate under acceleration. Essentially, it computes how quickly a particle settles to the bottom of a solution. In terms of the time dimension, a Svedberg unit amounts to exactly 10−13 seconds, indicating that it is essentially a measure of time.
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. 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.
7. In recent times, the “dynamic brake system” is becoming popular in modern railways. The dynamic brake system coverts Kinetic energy to__:
[A] Potential energy
[B] Electricity
[C] Sound energy
[D] Magnetic energy
Show Answer
Correct Answer: B [ Electricity]
Notes:
Modern engines also have, additionally, dynamic brake system which works on the principle of converting kinetic energy of the moving train to electricity making the electric motors to work as generators.
8. For any object on the surface of earth, which among the following properties will be directly proportional to each other?
[A] It’s acceleration and it’s mass
[B] It’s mass and it’s weight
[C] It’s weight and it’s acceleration
[D] It’s speed and it’s velocity
Show Answer
Correct Answer: B [ It’s mass and it’s weight]
Notes:
The weight of an object and its mass are directly proportional. For a given gravitational field strength, the greater the mass of the object, the greater its weight.
9. Which among the following provides potential energy to an object?
[A] Its momentum
[B] It’s position
[C] It’s acceleration
[D] It’s shape
Show Answer
Correct Answer: B [ It’s position]
Notes:
The potential energy is defined as the energy that is stored in an object due to its position. Various types of potential energy include the gravitational potential energy (depends on its mass and its distance from the center of other object’s mass), the elastic potential energy, the electric potential energy.
10. When you throw a ball with an angle to the horizontal (projectile); the ball has __:
[A] Uniform velocity in horizontal direction but uniform acceleration in vertical direction
[B] Uniform acceleration in horizontal direction but uniform velocity in vertical direction
[C] Uniform acceleration in both horizontal and vertical directions
[D] Uniform velocity in both horizontal and vertical directions
Show Answer
Correct Answer: A [ Uniform velocity in horizontal direction but uniform acceleration in vertical direction]
Notes:
The motion of a projectile is two dimensional motion consisting of (i) horizontal motion and (ii) vertical motion. Hence, at any instant, the velocity of a projectile has two components (i) horizontal component and (ii) vertical component. The horizontal component remains unchanged throughout the flight as there is no acceleration in horizontal direction. The vertical component is continuously affected by the force of gravity. Thus, the horizontal motion is uniform motion but the vertical motion is uniformly accelerated motion.)
