GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A There is a decrease in weight.
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B There is acceleration upwards.
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C There is an increase in speed.
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D There is movement upwards.
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Detailed explanation-1: -There is no resultant force and the skydiver reaches terminal velocity. When the parachute opens, the air resistance increases. The skydiver slows down until a new, lower terminal velocity is reached.
Detailed explanation-2: -Once the parachute is opened, the air resistance overwhelms the downward force of gravity. The net force and the acceleration on the falling skydiver is upward. An upward net force on a downward falling object would cause that object to slow down. The skydiver thus slows down.
Detailed explanation-3: -At a certain, very high, speed the upward drag force is equal to the pull of gravity on them. Once this speed is reached there is no more speeding up. The skydiver continues to fall at this terminal speed . The resultant force on the skydiver is zero: equilibrium.
Detailed explanation-4: -The velocity of the sky diver is greater than the terminal velocity before he opens the parachute since there is only gravitational force acting on the person. But suddenly when the parachute opens there is air resistance which acts opposite to the gravitational force and the velocity of the sky diver reduces.
Detailed explanation-5: -You’d have learned (yawningly) that the terminal velocity of a falling body occurs when the force exerted on it by gravity is exactly balanced by the force exerted on it by resistance, such that the body experiences zero acceleration.