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Question
What do you mean by free fall?
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Solution
- The gravity of the Earth attracts every object towards its centre.
- When an object is released from a height, it falls towards the surface of the earth under the influence of gravitational force.
- The motion of the object is said to have free fall.
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| We know that the force of gravity due to the earth acts on each and every object. When we were holding the stone in our hand, the stone was experiencing this force, but it was balanced by a force that we were applying on it in the opposite direction. As a result, the stone remained at rest. Once we release the stone from our hands, the only force that acts on it is the gravitational force of the earth and the stone falls down under its influence. Whenever an object moves under the influence of the force of gravity alone, it is said to be falling freely. Thus the released stone is in a free fall. In free fall, the initial velocity of the object is zero and goes on increasing due to the acceleration due to the gravity of the earth. During free fall, the frictional force due to air opposes the motion of the object and a buoyant force also acts on the object. Thus, true free fall is possible only in a vacuum. |
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The stone held in the hand is stable because on it ......- two unbalanced forces are exerted.
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