GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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True
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False
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Either A or B
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None of the above
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Detailed explanation-1: -The gravitational force of earth which pulls the balls towards the ground. Thus, the ball will fall on earth. Frictional force will also act on the ball due to the air resistance. Mechanical force is not acting on the ball.
Detailed explanation-2: -When you throw a ball up in the air, its direction/velocity on the way up, although it rises up into the air, is actually downward. On its way up, its speed decreases, until it momentarily stops at the very top of the balls motion. Its acceleration is-9.8 m/s^2 at the very top.
Detailed explanation-3: -At its maximum height, the speed of the ball is: Answer: 0 m/s. The instantaneous speed of any projectile at its maximum height is zero.
Detailed explanation-4: -For example, when a ball is thrown up in the air, the ball’s velocity is initially upward. Since gravity pulls the object toward the earth with a constant acceleration g, the magnitude of velocity decreases as the ball approaches maximum height.