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. 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.
2. Which among the following defines cohesive force?
[A] the force of attraction acting between the molecules of same material
[B] the force of attraction acting between the molecules of different material
[C] the force of attraction acting between the atoms of same material
[D] None of the above
Show Answer
Correct Answer: A [the force of attraction acting between the molecules of same material]
Notes:
The force of attraction acting between the molecules of same material is known as cohesive force. Cohesive force is the action or property of like molecules sticking together, being mutually attractive.
3. Which among the following is true about Total Internal Reflection?
[A] A ray passing from rarer to denser medium and not able to pass to denser medium at an angle greater than critical angle
[B] A ray passing from denser to rarer medium and not able to pass to rarer medium at an angle greater than critical angle
[C] A ray passing from either denser to rarer medium or rarer to denser medium and not able to pass any medium at an angle smaller than critical angle
[D] None of the above
Show Answer
Correct Answer: B [A ray passing from denser to rarer medium and not able to pass to rarer medium at an angle greater than critical angle]
Notes:
A ray passing from denser to rarer medium and not able to pass to rarer medium at an angle greater than critical angle. Critical angle is the angle in which the incident ray is 90 degrees to that of the refracted ray.
4. The term “Isopycnic” is most closely defined by which among the following?
[A] Two places with same atmospheric pressure
[B] Two liquids with same viscosity
[C] Two liquids with same density
[D] Two places with same temperature
Show Answer
Correct Answer: C [Two liquids with same density]
Notes:
The term “Isopycnic” refers to two substances having the same density. It is derived from the Greek words “iso,” meaning equal, and “pycnos,” meaning dense. In scientific contexts, isopycnic conditions are often used in centrifugation techniques to separate particles based on their density, such as in the purification of DNA or proteins.
5. 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.
6. What is the S.I unit of Coefficient of Mutual inductance?
[A] weber
[B] candela
[C] henry
[D] lambert
Show Answer
Correct Answer: C [ henry ]
Notes:
The unit of Coefficient of Mutual inductance is henry lambert is the S.I unit of Luminance weber is the S.I unit of Magnetic Flux candela is the S.I unit of Luminous Intensity
7. The magnitude of the resultant of two vectors is maximum in which of the following case?
[A] when vectors act in the same direction
[B] when vectors act in the opposite direction
[C] when vectors act at 90° to each other
[D] None of the above
Show Answer
Correct Answer: A [when vectors act in the same direction]
Notes:
The magnitude of the resultant of two vectors is maximum when vectors act in the same direction. The magnitude of the resultant of two vectors is minimum when vectors act in the opposite directions.
8. On which of the following quantities, Work done does not depend?
[A] Force applied
[B] Displacement
[C] Time
[D] Depends on all of the above
Show Answer
Correct Answer: C [Time]
Notes:
Work done does not depend on the time for which the force was applied. Work done is only dependant on the force and displacement. Time is involved in the case of Power only
9. What is the effect of increase in radius of orbit on the binding energy of a satellite?
[A] it increases
[B] it decreases
[C] It remains the same
[D] None of the above
Show Answer
Correct Answer: B [it decreases]
Notes:
The binding energy of a satellite decreases with the increase in the radius of orbit. The binding energy of a satellite is inversely proportional to the radius of orbit.
10. Which of the following is the unit of Strain?
[A] Newton
[B] Kg
[C] Watt
[D] None of the above
Show Answer
Correct Answer: D [None of the above]
Notes:
As Strain is the ratio of two like quantities, it has no dimensions and units. Strain = Change in configuration/Original configuration
