Force and Braking

• What does any moving object have?

  Kinetic energy
• What is the equation for kinetic energy?

  kinetic energy (J) = 1/2 x mass (kg) x velocity^2 (m/s)
• What happens to the kinetic energy if we double the velocity?

  It Quadruples
• What does kinetic energy depend on?

  velocity squared
• What happens to kinetic energy when a car brakes?

  All the kinetic energy is transferred into other forms of energy.
• What forces occur during braking?

  During braking, the brake presses against the wheel, the force of friction now acts between the brake and the wheel, the kinetic energy of the car is now converted into thermal energy in the brakes. This causes the temperature of the brakes to increase, at this time, the car slows down as it loses kinetic energy.
• How does an increase in speed affect the breaking force?

  The greater the speed, the greater the breaking force needed to stop the car in a certain distance.
• What does a large breaking force cause the car to do?

  Decelerate rapidly and causes a large amount of kinetic energy to be transferred to thermal energy in the brakes. This can cause the brakes to overheat and may cause the driver to lose control of the car.
• How do we calculate force?

  Force (N) = Mass (Kg) x Acceleration (m / s /s )