Assertion (A): A particle thrown upward has zero velocity at its upper...
Assertion (A): A particle thrown upward has zero velocity at its uppermost point.
Reason (R): The zero-velocity of a particle at any instant implies that the acceleration of the particle is also zero at that instant.
The correct answer is (a) Both A and R are true and R is the correct explanation of A.
Explanation:
• When a particle is thrown upward, it moves against the gravitational force of the earth.
• Due to this, the velocity of the particle decreases gradually until it reaches its maximum height.
• At the uppermost point, the particle stops for an instant and then starts falling back towards the earth due to the gravitational force.
• Thus, at the uppermost point, the velocity of the particle becomes zero.
• This is because the direction of velocity changes from upward to downward, and the particle goes through a momentary pause before it starts falling back towards the earth.
• At the point of zero velocity, the acceleration of the particle is also zero because the rate of change of velocity is zero.
• Therefore, both Assertion (A) and Reason (R) are true, and Reason (R) correctly explains Assertion (A).
• Hence, the correct answer is (a) Both A and R are true and R is the correct explanation of A.