Escape velocity from a planet of mass M and radius R is v. For another planet of mass 4M and radius 2R, escape velocity is MCQ with Answer and Explanation

Escape velocity from a planet of mass M and radius R is v. For another planet of mass 4M and radius 2R, escape velocity is
A. v/√2
B. v
C. √2 v
D. 2v
Answer: Option C
Solution (By JKExamLibrary)
v_esc ∝ √(M/R). New ∝ √(4M/2R) = √(2M/R) = √2 √(M/R) = √2 v.

This question belongs to: Science Physics

Discuss this Question (0)

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

Practice More Physics Questions

Question #1 Report Error
Which is the most penetrating radiation?
A. Alpha
B. X-rays
C. Beta
D. Gamma

Correct Answer: Option D


Explanation:
Gamma rays highest penetration, alpha least.

This question belongs to: Science Physics
Question #2 Report Error
A bullet of mass 20 g is fired with velocity 200 m/s. Its momentum is
A. 40 kg m/s
B. 4 kg m/s
C. 4000 kg m/s
D. 0.4 kg m/s

Correct Answer: Option B


Explanation:
Mass m = 20 g = 0.02 kg. Momentum p = m v = 0.02 × 200 = 4 kg m/s. Always convert mass to kg. Momentum unit kg·m/s.

This question belongs to: Science Physics
Question #3 Report Error
In the photoelectric effect, increasing the intensity of the incident light (while keeping frequency constant) will cause:
A. A change in the threshold frequency of the metal surface.
B. A decrease in the maximum kinetic energy of the emitted electrons.
C. An increase in the maximum kinetic energy of the emitted electrons.
D. An increase in the number of emitted photoelectrons per second.

Correct Answer: Option D


Explanation:
According to Einstein's photoelectric equation, the kinetic energy of emitted electrons depends exclusively on the frequency of the incident light and the metal's work function. Intensity represents the number of photons striking the surface per second. More photons mean more collisions with electrons, leading strictly to an increase in the number of emitted photoelectrons (photoelectric current), not their energy.

This question belongs to: Science Physics