forces acting on a skydiver

• As soon as the skydiver jumps out of the plane, the only force acting is weight due to gravity
• The weight force will not change during the journey
• Due to weight


  The skydiver experiences a resultant force acting downwards
• The skydiver experiences friction with air molecules

  This force is called air resistance and it acts upwards
• As the skydiver's velocity increases

  The air resistance also increases
• At a certain point

  The air resistance balances the weight
• Terminal velocity


  The velocity at which the air resistance balances the weight, so there is no resultant force and the velocity stays constant
• When the skydiver opens their parachute


  The surface area increases, causing air resistance to massively increase
• With increased air resistance greater than weight


  There is a resultant force acting upwards, causing the skydiver to decelerate
• As the velocity decreases


  The air resistance also decreases
• When air resistance balances weight again


  The resultant force is zero and the velocity stays constant at a lower terminal velocity
• Motion of a skydiver

  1. Jump out of plane

  2. Only weight force acts, skydiver accelerates

  3. Air resistance increases, skydiver reaches terminal velocity

  4. Parachute opens, air resistance increases, skydiver decelerates

  5. Lower terminal velocity reached before landing
• This is an important topic that often comes up in exams, so it should be learned off by heart