Physics 2 Unit 3

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Physics 2 Unit 3
2013-05-11 14:12:59

Work Energy Momentum
Show Answers:

  1. How is work calculated?
    Work = Force x (distance in the direction of the force)
  2. What is work measured in?
    Work is measured in joules
  3. How is power calculated?
    Power = Energy ➗ time
  4. What is meant by gravitational potential energy?
    Gravitational potential energy is the energy stored in an object because of its position I'm a gravitational field
  5. How is the change in gravitational potential energy calculated?
    Ep = m x g x h

    • Ep = change in gravitational potential energy /J
    • m = mass /kg
    • g = gravitational field strength per kilogram / N/Kg
    • h = change in height in metres
  6. How is kinetic energy calculated?
    Ek = 1/2 x m x v" (squared)

    • Ek = kinetic energy
    • m = mass
    • v = speed
  7. How is momentum calculated?
    P = m x v

    • P = momentum kgm/s
    • m = mass
    • v = velocity
  8. What is meant by the conservation momentum?
    The total momentum before the interaction is equal to the total momentum afterwards - providing that no external forces act on them
  9. What is the function of the crumple zone in cars?
    Crumple zones in cars are designed to fold in a collision. This increases the impact time and so reduced the force on the car and people in it