Question

ASSERTION : The time of ascent for a body projected to move up a rough inclined plane is less than the time of descent.
REASON : The retardation for upward motion is more than the acceleration for downward motion.

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

Answer 1

The correct option is A Both Assertion and Reason are true and Reason is the correct explanation of Assertion

Let acceleration due to gravity be $g$ and acceleration due to friction be $f$. $f$ is the same in both cases.
While moving up: the opposing forces are gravity + friction
So, net retardation $=g+f$

While moving down: it is only friction and gravity is the supporting force.
So, net acceleration $=g-f$

Statement II is true.

So, the time of ascent for a body projected to move up a rough inclined plane is less than the time of decent as it receives more retardation.
Statement I is also true.