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. These questions are part of GKToday’s 35000+ MCQs Bank Course in GKToday Android App
21. What kind of waves are produced in a cylinder containing a liquid by moving its piston back and forth?
[A] Transverse
[B] Longitudinal
[C] Transverse or longitudinal
[D] None of the above
Show Answer
Correct Answer: B [Longitudinal]
Notes:
Longitudinal waves are produced in a cylinder containing a liquid by moving its piston back and forth.
22. What is the measure of the response of the ear to the sound known as?
[A] Pitch
[B] Intensity
[C] Loudness
[D] Amplitude
Show Answer
Correct Answer: C [Loudness]
Notes:
Loudness is a measure of the response of the ear to the sound. Even when two sounds are of equal intensity, we may hear one as louder than the other simply because our ear detects it better.
23. Which of the following principles is used to define the First law of Thermodynamics?
[A] Conservation of mass
[B] Conservation of energy
[C] Conservation of momentum
[D] Conservation of charge
Show Answer
Correct Answer: B [Conservation of energy]
Notes:
The first law of thermodynamics is the general law of conservation of energy applied to any system in which energy transfer from or to the surroundings (through heat and work) is taken into account.
24. Which of the following is true about a cyclic process?
[A] the total heat absorbed equals the work done by the system.
[B] the system returns to its initial state
[C] Both a and b
[D] None
Show Answer
Correct Answer: C [Both a and b]
Notes:
In a cyclic process, the system returns to its initial state and the total heat absorbed equals the work done by the system.
25. What of the following represents linear magnification?
[A] ratio of the height of the image to the height of the object
[B] ratio of the height of the object to the height of the image
[C] product of the height of the object to the height of the image
[D] difference of the height of the image to the height of the object
Show Answer
Correct Answer: A [ratio of the height of the image to the height of the object]
Notes:
The linear magnification (m) is defined as the ratio of the height of the image to the height of the object.
26. What part of eyes give it a distinctive colour?
[A] Cornea
[B] Iris
[C] Pupil
[D] Retina
Show Answer
Correct Answer: B [Iris]
Notes:
The iris is that part of eye which gives it its distinctive colour.
27. How many electrons constitutes a 1 coulomb charge?
[A] 3 × 1016
[B] 6 × 1018
[C] 9 × 1021
[D] 1
Show Answer
Correct Answer: B [6 × 1018 ]
Notes:
1 coulomb(C) of charge is equivalent to the charge contained in approximately 6 × 1018 electrons. An electron possesses a negative charge of 1.6 X 10-19c. Coulomb is the S.I unit of electric charge.
28. Which of the following is correct NOT correct about inert electrodes?
[A] They serve as source of electrons
[B] They take part in the chemical reaction
[C] Both a and b
[D] None of the above
Show Answer
Correct Answer: B [They take part in the chemical reaction]
Notes:
An inert electrode is a metal submerged in an aqueous solution of ion compounds that transfers electrons rather than exchanging ions with the aqueous solution. It does not participate or interfere in the chemical reaction but serves as a source of electrons.
29. Which of these is NOT a product of a fuel cell?
[A] Water
[B] Electricity
[C] Heat
[D] None of the above
Show Answer
Correct Answer: D [None of the above]
Notes:
The products of the reaction in the cell are water, electricity, and heat.
30. What is the output of an OR gate when both the inputs are 1?
[A] 0
[B] 1
[C] Either 0 or 1
[D] None
Show Answer
Correct Answer: B [1]
Notes:
The OR gate is a digital logic gate that gives a HIGH output if one or both the inputs to the gate are HIGH.
