Central Exam — General Science — Physics
UPSC · SSC · Bank · Railway · NDA — Central Government Exam MCQ Practice
Showing 1–10 of 106 questions
in Physics
Q.1
Medium
Physics
The escape velocity from the surface of a planet depends on which two fundamental properties of that planet?
Correct Answer:
B. Mass and radius
Explanation:
Escape velocity is mathematically derived as v = √(2GM/R), where G is gravitational constant, M is the planet's mass, and R is its radius.
These two properties directly determine the gravitational field strength at the planet's surface, which defines the minimum velocity needed to escape gravitational attraction.
Q.2
Easy
Physics
Newton first law also called?
Correct Answer:
C. Law of inertia
Explanation:
First law = Law of Inertia.
Q.3
Easy
Physics
Unit of electric current?
Correct Answer:
C. Ampere
Explanation:
Current measured in Amperes.
Q.4
Medium
Physics
Speed of sound in air?
Correct Answer:
B. 343 m/s
Explanation:
~343 m/s at 20°C.
Q.6
Easy
Physics
Sound cannot travel through?
Correct Answer:
C. Vacuum
Explanation:
Sound needs medium, not vacuum.
Q.7
Easy
Physics
A body is thrown vertically upward with a velocity of 40 m/s. What is the maximum height reached? (Take g = 10 m/s²)
Correct Answer:
A. 80 m
Explanation:
Using v² = u² - 2gh, where final velocity v = 0, u = 40 m/s, g = 10 m/s². We get h = 1600/20 = 80 m
Q.8
Easy
Physics
Which of the following is NOT a SI base unit?
Correct Answer:
C. Newton
Explanation:
Newton is a derived unit (kg⋅m⋅s⁻²). Ampere, Kelvin, and Mole are SI base units
Q.9
Easy
Physics
A car moving at 20 m/s suddenly applies brakes with deceleration of 5 m/s². How far does it travel before stopping?
Correct Answer:
B. 40 m
Explanation:
Using v² = u² + 2as, where v = 0, u = 20 m/s, a = -5 m/s². We get s = 400/10 = 40 m
Q.10
Easy
Physics
What is the SI unit of pressure?
Correct Answer:
B. Pascal
Explanation:
Pascal (Pa) is the SI unit of pressure, equal to 1 N/m²