# General Science – Physics MCQs

Physics Objective (Multiple Choice) General Knowledge & General Science Questions & Answers for SSC-CGL, UPPSC, UPSC, NDA, CDS and UPSC Civil Services Prelims Examinations.

31. Which of the following instruments is used to measure the relative density of a liquid?

[A] Hydrometer
[B] Hygrometer
[C] Lactometer
[D] Gravitimeter

32. What is the density of air at room temperature?

[A] 1.41
[B] 1.75
[C] 1.29
[D] 1.9

33. What is the Gaussian unit of kinematic viscosity?

[A] Henry
[B] Stokes
[C] poiseiulle
[D] Watt

34. What is the S.I unit of frequency?

[A] Second
[B] Watt
[C] Hertz
[D] Joule

35. What happens to the frequency of the pendulum if it is suspended from the ceiling of the lift moving up ward with constant acceleration?

[A] it decreases
[B] it increases
[C] may increase or decrease
[D] No change

36. What is the motion in which a body moves to and fro repeatedly about a fixed point in a definite interval of time known as?

[A] Circulatory Motion
[B] Rotary Motion
[C] Linear Motion
[D] Oscillatory Motion

37. Which of the following is correct about transverse mechanical waves?

[A] they can travel through solids and gases
[B] they can travel through solids but not liquids
[C] they can travel through solids and liquids
[D] they can travel through gases but not solids

38. Which of the following waves is produced when inner shell electrons in atoms move from one energy level to a lower level?

[A] Infrared
[B] X-rays
[C] Ultraviolet
[D] Microwaves

39. Which of the following is correct about mechanical waves?

[A] they require a medium to propagate
[B] they don’t require a medium to propagate
[C] may or may not require a medium to propagate
[D] None of the above