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Assertion: A boy facing forward in a bus...

Assertion: A boy facing forward in a bus throws a ball straight up. At the same instant the bus begins to accelerate. The ball goes up and falls in front of the boy.
Reason: As the ball rises, it does not continue at a constant velocity

A

IF both assertion and reason are true and reason is the correct explanation of assertion

B

If both assertion and reason are true but reason is not the correct explanation of assertion

C

If assertion is true but reason is false

D

If assertion is false but reason is true

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason question, we will analyze both the assertion and the reason step by step. ### Step 1: Understand the Assertion The assertion states that a boy in a bus throws a ball straight up, and when the bus accelerates, the ball falls in front of the boy. ### Step 2: Analyze the Situation When the boy throws the ball straight up, it initially has the same horizontal velocity as the bus due to inertia. However, when the bus starts to accelerate, the boy (and the bus) moves forward faster than the ball, which continues to move at its initial horizontal velocity. ### Step 3: Conclusion from the Assertion Since the ball does not have any horizontal force acting on it after being thrown, it will not accelerate forward with the bus. Therefore, while the bus moves forward, the ball will appear to fall behind the boy, landing in front of him. ### Step 4: Understand the Reason The reason states that as the ball rises, it does not continue at a constant velocity. This is true because while the horizontal component of the ball's motion remains constant, the vertical component changes due to the acceleration due to gravity. ### Step 5: Analyze the Reason The vertical velocity of the ball decreases as it rises until it reaches its peak (where the vertical velocity is zero) and then increases as it falls back down. Thus, the overall velocity of the ball is not constant because the vertical component is changing. ### Step 6: Conclusion from the Reason Since the vertical component of the ball's velocity is changing, the overall motion of the ball is not at a constant velocity. ### Final Conclusion - The assertion is **false** because the ball does not fall in front of the boy; it falls behind him. - The reason is **true** because the ball does not maintain a constant velocity due to the changing vertical component. ### Answer: - Assertion: False - Reason: True
To solve the assertion and reason question, we will analyze both the assertion and the reason step by step. ### Step 1: Understand the Assertion The assertion states that a boy in a bus throws a ball straight up, and when the bus accelerates, the ball falls in front of the boy. ### Step 2: Analyze the Situation When the boy throws the ball straight up, it initially has the same horizontal velocity as the bus due to inertia. However, when the bus starts to accelerate, the boy (and the bus) moves forward faster than the ball, which continues to move at its initial horizontal velocity. ...
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