At what depth below the surface of the Earth does the acceleration due to gravity become zero? MCQ with Answer and Explanation

Question

Share Report Error

At what depth below the surface of the Earth does the acceleration due to gravity become zero?

A. It never becomes zero

B. At a depth equal to one-fourth the radius of the Earth

C. At the center of the Earth

D. At a depth equal to half the radius of the Earth

Answer: Option C

Solution (By JKExamLibrary)

The acceleration due to gravity at a depth 'd' is given by g' = g(1 - d/R), where R is the radius of the Earth. If we go to the center of the Earth, the depth 'd' becomes exactly equal to R. Substituting d = R into the formula gives g' = g(1 - R/R) = g(1 - 1) = 0. So, gravity is zero at the core.

This question belongs to: Science Physics

Request complete Subject PDF

Discuss this Question (0)

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

Practice More Physics Questions

Question #1

Share Report

A bus travels the first 20 km at 40 km/h and the next 20 km at 60 km/h. Average speed is

A. 52 km/h

B. 48 km/h

C. 45 km/h

D. 50 km/h

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option B

Explanation:
Time1 = 20/40=0.5 h, Time2=20/60=1/3 h. Total time=5/6 h. Total distance=40 km. Avg speed=40/(5/6)=48 km/h. Not arithmetic mean.

This question belongs to: Science Physics

Question #2

Share Report

The velocity of light in vacuum is 3×10⁸ m/s. In a medium of refractive index 1.5, speed is

A. 3×10⁸ m/s

B. 1.5×10⁸ m/s

C. 4.5×10⁸ m/s

D. 2×10⁸ m/s

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option D

Explanation:
v = c/n = 3×10⁸/1.5 = 2×10⁸ m/s.

This question belongs to: Science Physics

Question #3

Share Report

The heating effect of electric current is utilised in

A. Galvanometer

B. Electric generator

C. Electric motor

D. Electric fuse

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option D

Explanation:
Fuse uses heating effect (Joule heating I²R). When current exceeds limit, fuse wire melts due to heat, breaking circuit. Motor uses magnetic effect, generator uses electromagnetic induction, galvanometer detects current. Iron box, heater also use heating effect.

This question belongs to: Science Physics

Explore All Physics MCQs