Question

Assertion: An astronaut in an orbiting space station above the earth experiences weightlessness.
Reason: An object moving around the earth under the influence of earth’s gravitational force is in a state of ‘free fall’.

A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C. Assertion is correct but Reason is incorrect
D. Both assertion and Reason are incorrect

Answer 1

Think about under what condition, a space station can orbit around the earth. And what happens if you do not feel the earth’s gravitational field applying any force on you.

Complete step by step answer: An object moving around the earth experiences centripetal acceleration due to the gravitational force. An astronaut in the space station experiences the two forces namely, centripetal force, away from the earth and gravitational force, towards the earth.
The object is neither going away from the earth not falling on the earth. That means, both the forces are cancelling each other out. Therefore, there is no gravitational force acting on the object now. And since, weight is felt because of the gravitational force of earth, once the gravitational force is cancelled out, the body starts to feel weightlessness.
Hence, the astronaut in an orbiting space station above the earth experiences the weightlessness condition.
From the above explanation, we can conclude that the assertion given in the question is correct.
We also know that the body that falls towards the ground due to earth’s gravitational force is said to be in the state of free fall because no other force is being applied on it.
So, the reason is also correct.
But we can observe that the reason is not the correct explanation of the assertion.
Therefore, from the above explanation, the correct answer is, option (B) Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion

Note: If the centripetal force is greater than the earth's gravitational force, then the object will leave the earth's gravitational field and go into space. Satellites on mars are sent using this concept. The minimum energy required to leave the earth’s gravitational field is called binding energy.