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. The ideal fluid which is a hypothetical fluid should contain _______?
[A] Zero Viscosity Only
[B] Zero Compressibility Only
[C] Zero Viscosity & Zero Compressibility
[D] None of the above
Show Answer
Correct Answer: C [Zero Viscosity & Zero Compressibility]
Notes:
An ideal fluid hypothetical fluid should contain Zero Viscosity & Zero Compressibility. Almost all fluids will not have zero viscosity and zero compressibility.
2. 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.
3. Electron microscope works on which of the following principles?
[A] Optical interference
[B] Wave Nature of electrons
[C] Motion of charged particle in electromagnetic fields
[D] Faraday’s law of Electromagnetic induction
Show Answer
Correct Answer: B [Wave Nature of electrons]
Notes:
Electron microscope works on the principle of Wave Nature of electrons. Electron microscopes use an electron beam instead of visible light and an electron detector instead of our eyes. An electron beam allows us to see at very small scales because electrons can also behave as light due to its wave nature.
4. The motion of an object under free fall is an example of which of the following?
[A] uniform velocity
[B] uniform acceleration
[C] zero acceleration
[D] non-uniform acceleration
Show Answer
Correct Answer: B [uniform acceleration]
Notes:
The motion of an object under free fall is a case of uniform acceleration. If an object is released from a height near the surface of earth, it accelerates downwards under the influence of a gravity pull with acceleration due to gravity.
5. The equation of motion ‘v = u +at’ can be applied in which of the following cases?
[A] simple harmonic motion
[B] circular motion
[C] when acceleration is constant
[D] Both b and c
Show Answer
Correct Answer: C [when acceleration is constant]
Notes:
The equation of motion ‘v = u +at’ can be applied only when the acceleration is constant. It cannot be applied in the cases of simple harmonic motion and circular motion.
6. What is the maximum height that can be attained by a projectile?
[A] equal to its maximum range
[B] one half of its maximum range
[C] one-fourth of its maximum range
[D] twice of its maximum range
Show Answer
Correct Answer: C [one-fourth of its maximum range]
Notes:
The maximum height that can be attained by a projectile is equal to one-fourth of its maximum range.
7. The force acting on a body for a short time are called as:
[A] Average force
[B] Momentum
[C] Impulse
[D] Tension
Show Answer
Correct Answer: C [Impulse]
Notes:
The force acting on a body for a short time are called as Impulse. Example: hitting a ball with a bat. Impulse = average force x time It is a measure of total effect of the force. Its unit is Ns
8. 1 kilogram force produces how much acceleration in a body of mass 1 kg?
[A] 1 ms-2
[B] 0
[C] 9.8 ms-2
[D] -1 ms-2
Show Answer
Correct Answer: C [9.8 ms-2]
Notes:
1 Kilogram force or 1 Kilogram weight is that much force which produces an acceleration of 9.8 ms-2 in a body of mass 1 kg. Also, 1 kg wt. or 1 kg f = 9.8 N
9. Work done will NOT be zero in which of the following case/cases?
[A] When displacement is zero
[B] When angle between force and displacement vector is zero
[C] When angle between force and displacement vector is 90°
[D] When force is zero
Show Answer
Correct Answer: B [When angle between force and displacement vector is zero]
Notes:
Work done will be zero: 1. When displacement is zero 2. When force is zero 3. When angle between force and displacement vector is zero
10. Kepler’s second law is also known as:
[A] Law of periods
[B] Law of areas
[C] Law of orbits
[D] Law of Planets
Show Answer
Correct Answer: B [Law of areas]
Notes:
Kepler’s second law states that an imaginary line joining a planet and the sun sweeps out an equal area of space in equal amounts of time i.e. the areal velocity of the planet around the sun is constant. It is also known as Law of areas.
