When you let go of an object, why does it fall towards to the ground?

Gravity exerts a force called weight on the object, which causes it to accelerate towards the earth, and so move downwards.

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What is meant by the term 'terminal velocity'?

Terminal velocity is the maximum velocity attainable by an object as it falls through a fluid (either a liquid or gas). 

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Why does a skydiver reach terminal velocity?

When the weight of the skydiver is equal to the air resistance acting on them, they fall at a constant velocity.

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What happens to the air resistance acting on a falling object as it accelerates towards the ground?

It increases

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What is the net force acting on an object travelling at terminal velocity?

Zero


At terminal velocity the driving force is equal to the resistive forces.

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When a parachutist opens their parachute, what happens to the air resistance?

Air resistance increases.

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What is the name of the force opposing a falling object?

Air Resistance  OR  Drag

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What is the acceleration of skydiver when they are travelling at terminal velocity?

Zero

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What causes air resistance?

The force of air resistance is caused by a moving object colliding with particles in the air.

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Why do falling objects reach terminal velocity?

  1. As an object accelerates and its velocity increases, the force of the air resistance will also increase.
  2. At some point, the force of weight acting downwards will equal the air resistance upwards, so there will be no resultant force.
  3. This means that there will no longer be any acceleration and the velocity of the object will stay constant.

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