Change in momentum

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

  Force due to change in momentum
• How do safety features like seat belts reduce dangers?

  They reduce the forces from momentum changes
• Who is the target audience for this video?

  Triple physics students
• What is momentum calculated by?

  Mass multiplied by velocity
• Why can rapid changes in momentum be dangerous?

  They can create huge forces on passengers
• What happens to the momentum of passengers during a crash?

  It falls from a large amount to zero
• What do crash tests help manufacturers design?

  Safety features like seat belts
• What is the time frame for momentum change during a crash?

  Less than a second
• How do you calculate the force acting on an object?

  Mass multiplied by acceleration
• How is acceleration calculated?

  Change in velocity divided by time
• What is the combined equation for calculating force?

  Force equals mass times change in velocity over time
• What does mass multiplied by change in velocity represent?

  Change in momentum
• Is the force equation provided in the exam?

  Yes, it is given
• If a man has a mass of 100 kg and the car stops in 1 second, what is the force experienced?

  3000 Newtons
• What can rapid changes in momentum lead to?

  Huge forces that can be fatal
• How can we reduce the danger of rapid momentum changes?

  By extending the time of momentum change
• What are some safety devices that slow down momentum change?

  • Airbags
  • Seatbelts
  • Crash mats
  • Bike helmets
  • Cushion surfaces in playgrounds
• What is the risk associated with huge forces during a crash?

  Serious injury or fatality
• What is the effect of safety devices on forces acting during a crash?

  They reduce the forces acting on passengers
• Why is it important to slow down momentum change?

  To reduce the risk of serious injury