Forces acting on a skydiver

• What should you be able to describe by the end of the video?

  Forces acting on a skydiver with velocity
• What is the only force acting on a skydiver immediately after jumping?

  Weight due to gravity
• How does the resultant force change as the skydiver falls?

  The resultant force acts downwards initially
• What happens to the skydiver as they accelerate towards the ground?

  They experience a resultant force acting downwards
• What force opposes the skydiver's fall?

  Air resistance
• What occurs as the skydiver's velocity increases?

  Air resistance also increases
• What happens when air resistance balances weight?

  The resultant force becomes zero
• What is the term for when the skydiver's velocity stays constant?

  Terminal velocity
• What happens when the skydiver opens their parachute?

  Air resistance massively increases
• What is the effect of increased surface area from the parachute?

  It causes air resistance to increase
• What happens when air resistance becomes greater than weight after opening the parachute?

  The resultant force acts upwards
• What does the skydiver experience after the parachute opens?

  The skydiver decelerates
• How does the velocity change after the parachute opens?

  The velocity decreases
• What happens to air resistance as the skydiver's velocity decreases?

  Air resistance also decreases
• What occurs when air resistance balances weight again after parachute deployment?

  The resultant force is zero
• What is the new terminal velocity after the parachute opens?

  A lower terminal velocity
• What happens when the skydiver lands?

  The skydiver reaches the ground safely
• What are the stages of a skydiver's fall?

  1. Jumping out: Only weight acts downwards.
  2. Accelerating: Weight > air resistance, accelerates downwards.
  3. Terminal velocity: Air resistance balances weight, constant velocity.
  4. Parachute opens: Air resistance increases, deceleration occurs.
  5. Lower terminal velocity: Air resistance balances weight again, constant but lower velocity.
  6. Landing: Skydiver reaches the ground safely.
• How can the motion of a skydiver be represented graphically?

  • Velocity-time graph
  • Initial acceleration phase
  • Constant velocity at terminal velocity
  • Deceleration after parachute opens
  • New constant velocity at lower terminal velocity