69 808
Assignments Done
99,5%
Successfully Done
In February 2019

Answer to Question #66352 in Mechanics | Relativity for Irshad

Question #66352
Define weightlessness and explain its conditions by using example.
Expert's answer
Weightlessness, or an absence of 'weight', is an absence of stress and strain resulting from externally applied mechanical contact-forces, typically normal forces from floors, seats, beds, scales, and the like. Counterintuitively, a uniform gravitational field does not by itself cause stress or strain, and a body in free fall in such an environment experiences no g-force acceleration and feels weightless. This is also termed "zero-g" where the term is more correctly understood as meaning "zero g-force."
When bodies are acted upon by non-gravitational forces, as in a centrifuge, a rotating space station, or within a space ship with rockets firing, a sensation of weight is produced, as the contact forces from the moving structure act to overcome the body's inertia. In such cases, a sensation of weight, in the sense of a state of stress can occur, even if the gravitational field were zero. In such cases, g-forces are felt, and bodies are not weightless.
When the gravitational field is non-uniform, a body in free fall suffers tidal effects and is not stress-free. Near a black hole, such tidal effects can be very strong. In the case of the Earth, the effects are minor, especially on objects of relatively small dimension (such as the human body or a spacecraft) and the overall sensation of weightlessness in these cases is preserved. This condition is known as microgravity and it prevails in orbiting spacecraft.

https://en.wikipedia.org/wiki/Weightlessness

Need a fast expert's response?

Submit order

and get a quick answer at the best price

for any assignment or question with DETAILED EXPLANATIONS!

Comments

Assignment Expert
20.03.17, 16:20

Dear Irshad,

You're welcome. We are glad to be helpful.
If you liked our service please press like-button beside answer field. Thank you!

Irshad
18.03.17, 05:59

Thank you

Leave a comment

Ask Your question

Submit
Privacy policy Terms and Conditions