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 eye defect causes image focus in front of the retina?
[A] Presbyopia
[B] Hypertropia
[C] Myopia
[D] Hyperopia
Show Answer
Correct Answer: C [Myopia]
Notes:
Myopia (short-sightedness) occurs when images are focused in front of the retina, causing distant objects to appear blurry. It is commonly due to an elongated eyeball or excessive corneal curvature. This defect is corrected using concave (diverging) lenses. Hyperopia, by contrast, focuses images behind the retina.
2. 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.
3. At which of the following places water shall boil at the lowest temperature?
[A] Kochi
[B] Ooty
[C] Mount Abu
[D] New Delhi
Show Answer
Correct Answer: B [Ooty]
Notes:
This question is related to Antoine equation. Water to get boil, its vapour pressure must reach to its surrounding pressure. In a pressure cooker, it boils at the highest temperature. Elevation of Kochi is 0 m, ooty is 2,486 m, Mount Abu is 1,200 m, New Delhi is 216 m, Shimla is 2,205 m. So comparing all of them, water will boil at lowest temperature at ooty, followed by Shimla, Mount Abu , New Delhi and Kochi. This is because , higher we go lower is the atmospheric pressure and lower is the point where water`s vapour pressure gets equal to the atmospheric pressure.
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. With reference to a swinging pendulum, which among the following statements is correct when it is at bottom (middle of arc)?
[A] It has maximum kinetic energy and minimum potential energy
[B] It has maximum potential energy and minimum kinetic energy
[C] It has zero kinetic energy
[D] It has zero total energy
Show Answer
Correct Answer: A [ It has maximum kinetic energy and minimum potential energy]
Notes:
At the lowest point of its motion of swinging pendulum, kinetic energy is maximum and gravitational potential energy is minimum. At the highest point of its motion, kinetic energy is minimum and gravitational potential energy is maximum.
6. What is the rate of acceleration produced by 1 dyne force acting on a body of mass 1 gram?
[A] 9.8 m s-2
[B] 1 m s-2
[C] 1 cm s-2
[D] 9.8 cm s-2
Show Answer
Correct Answer: C [1 cm s-2]
Notes:
One dyne force is that much force which produces an acceleration of 1 cm s-2 in a body of mass one gram. 1 dyne = 1 g cm s-2 Also, 1 N = 105 dyne
7. Which of the following is correct about Gravitational force?
[A] It is always attractive in nature
[B] It is always repulsive in nature
[C] It may or may not be attractive in nature
[D] None of the above
Show Answer
Correct Answer: A [It is always attractive in nature]
Notes:
The Gravitational force is always attractive in nature while electric and magnetic force can be attractive or repulsive. It is the weakest force in nature.
8. What is the S.I unit of frequency?
[A] Second
[B] Watt
[C] Hertz
[D] Joule
Show Answer
Correct Answer: C [Hertz]
Notes:
The frequency is defined as the number of periodic motions executed by body per second. The S.I unit of frequency is hertz (Hz).
9. Which of these is correct about Simple Harmonic Motion?
[A] Restoring force is directly proportional to the displacement from mean position
[B] Restoring force is equal to the displacement from mean position
[C] Restoring force is inversely proportional to the displacement from mean position
[D] Restoring force is half of the displacement from mean position
Show Answer
Correct Answer: A [Restoring force is directly proportional to the displacement from mean position]
Notes:
Simple harmonic motion is a special type of periodic motion, in which a particle moves to and fro repeatedly about a mean position under a restoring force which is always directed towards the mean position and whose magnitude at any instant is directly proportional to the displacement of the particle from the mean position at that instant. Restoring force Displacement of the particle from mean position.
10. Which of the following about S.H.M is correct?
[A] In S.H.M. acceleration is maximum at extreme position
[B] In S.H.M. velocity is minimum at extreme position
[C] Both a and b
[D] None of the above
Show Answer
Correct Answer: C [Both a and b]
Notes:
In S.H.M: 1. acceleration is maximum at extreme position. 2. velocity is minimum at extreme position. 3. Direction of velocity is either towards or away from mean position depending on the position of particle.
