The working of a rocket is based on MCQ with Answer and Explanation

The working of a rocket is based on
A. Conservation of energy
B. Law of gravitation
C. Newton's first law
D. Conservation of linear momentum
Answer: Option D
Solution (By JKExamLibrary)
Rocket propulsion: momentum of exhaust gases equals momentum gained by rocket.

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Physics Questions

Question #1
The minimum distance to hear an echo (persistence of hearing 0.1 s, speed 340 m/s) is
A. 68 m
B. 34 m
C. 17 m
D. 10 m

Correct Answer: Option C


Explanation:
d = (v×t)/2 = (340×0.1)/2 = 17 m.

This question belongs to: Science Physics
Question #2
A body is projected vertically upwards with initial velocity u. The time taken to reach maximum height is:
A. u/(2g)
B. g/u
C. 2u/g
D. u/g

Correct Answer: Option D


Explanation:
At maximum height, final velocity v = 0. Using v = u - gt (taking upward positive), 0 = u - gt ⇒ t = u/g. This is time of ascent. Total time of flight would be 2u/g. The equation derives from Newton's first equation of motion under constant acceleration g downward. Memory aid: Time to peak = initial velocity / gravitational acceleration. This fundamental result appears in projectile motion problems. Competitive exams often combine this with energy conservation or symmetry concepts for advanced questions.

This question belongs to: Science Physics
Question #3
A force of 10 N acts on a body of mass 2 kg for 1 s. Change in momentum is
A. 5 kg m/s
B. 10 kg m/s
C. 20 kg m/s
D. 2 kg m/s

Correct Answer: Option B


Explanation:
Impulse = F t = 10 N s = change in momentum.

This question belongs to: Science Physics