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 radiations in the Sunlight causes tanning and sunburn?
[A] Ultraviolet
[B] Visible
[C] Infrared
[D] Micro waves
Show Answer
Correct Answer: A [Ultraviolet]
Notes:
The sunlight that reaches the earth has ultraviolet A and ultraviolet B (UVA and UVB) rays. These ultraviolet rays are the main causes of damage to the skin from the sun. UVA and UVB rays affect the skin’s sensitivity to sun exposure in different ways.
2. India’s first Nobel Prize for Physics was claimed in 1930 by the renowned physicist Sir C.V. Raman for his work in which among the following fields?
[A] Particle Physics
[B] Optics
[C] Thermodynamics
[D] Quantum Mechanics
Show Answer
Correct Answer: B [Optics]
Notes:
In 1930, C.V. Raman became the first person from Asia to be awarded a Nobel Prize in any field of science. CV Raman made significant contributions to the field of optics. He is best known for his discovery of the Raman effect, which is the scattering of light by molecules. This phenomenon is now known as Raman scattering. The date of the discovery, February 28, is now celebrated as National Science Day in India.
3. What is the mean value of g at earth’s surface?
[A] 0.98 meter per second
[B] 9.8 meter per second
[C] 9.8 meter per second square
[D] 0.98 meter per second square
Show Answer
Correct Answer: C [9.8 meter per second square]
Notes:
The mean value of the acceleration due to gravity (often denoted as “g”) at Earth’s surface is approximately 9.81 meters per second squared (m/s²). This value represents the average gravitational acceleration experienced by objects on the surface of the Earth. It is important to note that this value is not constant everywhere on Earth’s surface and can vary slightly due to factors such as location, altitude, and the density of the Earth’s crust.
4. What happens when a ship enters a Sea from a river ?
[A] It rises
[B] It remains at the same level
[C] sinks a little
[D] None of the above
Show Answer
Correct Answer: A [It rises]
Notes:
When a ship enters a sea from a river ,the ship is elevated or uplifted due to the density of sea water and during the buoyant motion of the ship, as it would gain both potential and kinetic energy when rising in the fluid.
5. Where will the weight of a person be maximum?
[A] At the Poles
[B] At the Tropic of Capricorn
[C] At the Tropic of Cancer
[D] At the Equator
Show Answer
Correct Answer: A [At the Poles]
Notes:
The weight of a person would be maximum at the poles, due to the higher gravitational force acting upon them in these regions. This occurs because Earth is an oblate spheroid, flattened at its poles and bulging at the equator, resulting in a shorter distance from the Earth’s center at the poles and a consequent higher gravitational pull. At the equator, the force is slightly weaker due to a greater distance from the Earth’s center. Weights at the Tropics of Cancer and Capricorn lie in-between the poles and equator, but are closer to the equator’s value.
6. In context with electromagnetism, which among the following is a correct definition of Permeability?
[A] Ability of a material to repel magnetic field within itself
[B] Ability of a material to support the formation of a magnetic field within another body
[C] Ability of a material to support the formation of a magnetic field within itself
[D] Ability of a material to create magnetic dipoles
Show Answer
Correct Answer: C [Ability of a material to support the formation of a magnetic field within itself]
Notes:
Ability of a material to support the formation of a magnetic field within itself is Permeability. It is the measure of the resistance of a material against the formation of a magnetic field.
7. The force between charged particles is called as:
[A] Nuclear Force
[B] Gravitational Force
[C] Centrifugal Force
[D] Electromagnetic Force
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Correct Answer: D [Electromagnetic Force]
Notes:
Electromagnetic force is the force between charged particles. It can be attractive for unlike charges and repulsive for like charges. It does not need any intervening medium to act and is enormously strong as compared to gravitational force.
8. 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.
9. Curie the a unit of which of the following?
[A] Luminescence
[B] Radioactivity
[C] Pressure
[D] Mass
Show Answer
Correct Answer: B [ Radioactivity ]
Notes:
The curie is a unit of ionizing radiation (radioactivity). It is symbolized with Ci . 1 curie = 3.7 x 10 10 disintegrations or nuclear transformations per second. This is approximately the amount of radioactivity emitted by one gram (1 g) of radium-226. The unit is named after Pierre Curie, a French physicist.
10. 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.
