You are here:

Physics/Weightless

Advertisement


Question
Hi Sir,

The is no gravity field inside a large hollow sphere...like in the centre of the Earth there is no gravity field..am I correct to say this. Hence weight is mass x g..therefore no g means no weight? Thanks!!

Answer
Hello ayee,

It is true that in the centre of the Earth there is no gravity field. So if a tunnel could be dug through the center of the Earth, an object at the center would have no weight. I need to comment on your statement "no gravity field inside a large hollow sphere". There is no gravity field at the center of a large hollow sphere.

And to be sure there's no misunderstanding, the sphere would not shield the contents of the sphere from an external gravity field. If you built a large hollow sphere here on the Earth's surface, you would not be weightless if you entered the sphere and went to the center. In fact, I should revisit my first statement about the center of the Earth. The Sun's pull would reach there.

I hope this helps,
Steve

Physics

All Answers


Answers by Expert:


Ask Experts

Volunteer


Steve Johnson

Expertise

I would be delighted to help with questions up through the first year of college Physics. Particularly Electricity, Electronics and Newtonian Mechanics (motion, acceleration etc.). I decline questions on relativity and Atomic Physics. I also could discuss the Space Shuttle and space flight in general.

Experience

I have a BS in Physics and an MS in Electrical Engineering. I am retired now. My professional career was in Electrical Engineering with considerable time spent working with accelerometers, gyroscopes and flight dynamics (Physics related topics) while working on the Space Shuttle. I gave formal classroom lessons to technical co-workers periodically over a several year period.

Education/Credentials
BS Physics, North Dakota State University
MS Electrical Engineering, North Dakota State University

©2016 About.com. All rights reserved.