Question

Assertion: The value of ‘g’ decreases as height increases from the surface of Earth.
Reason: ‘g’ depends on the mass of Earth.

• A. Both the assertion and the reason are true and the reason is the correct explanation of assertion.
• B. Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.
• C. Assertion is true, but the reason is false.
• D. Assertion is false, but the reason is true

Answer 1

The correct option is B Both the assertion and the reason are true, but the reason is not the correct explanation of the assertion.

$g=\frac{GM}{R^2}$
At a height h from the earth’s surface,
$g=\frac{\mathrm{GM}}{{(R+h)}^2}$
As the height increases from the surface of the earth , acceleration due to gravity decreases. Acceleration due to gravity depends also on the mass of the earth but it decreases with increase in height due to its inverse square relationship with distance.