P6 Q6

• Conservation of momentum allows complex collision problems to be solved without knowing about the forces involved?

  Collisions
• Information about the average force can be derived?

  Collisions
• Linear momentum of an object of mass moving with a velocity is defined as the product of the mass and the velocity?

  Momentum
• SI units are kg m/s?

  Momentum
• The direction of the momentum is the same as the _?

  Velocity
• Momentum is related to_?

  Kinetic Energy
• In order to change the momentum of an object, a force must be applied?

  Impulse
• The time rate change of momentum of an object is equal to the net force acting on it?

  Impulse
• Gives an alternative statement of Newton's second law?

  Impulse
• When a single, constant force acts on the object, there is an_derived to the object?

  Impulse
• SI unit of impulse is?

  kg m/s
• States that the impulse acting on the object is equal to the change in momentum of the object?

  Impulse-Momentum Theorem
• If the force is not constant, use the_ applied?

  Average force
• Can be thought of as the constant force that would give the same impulse to the object?

  Average force
• The impulse imparted by a force during the time interval is equal to the area under the force-time graph from the beginning to the end?

  Average force
• The impulse is equal to the average force multiplied by the time interval?

  Average force
• Increasing this time will _ the chance of dying in a car crash?

  reduce
• Ways to increase the time?

  Seat belts, air bags
• Restrain people so it takes more time?

  Seat belts
• New time is about _ seconds?

  0.15
• New force is about _ kN?

  9.8
• Increases the time of the collision?

  Air bags
• Spread out the area of contact and decreases the pressure?

  Air bags
• Momentum in an isolated system in which a collision occurs is conserved?

  Conservation of Momentum
• A _ may be the result of physical contact between two objects?

  Collision
• _ may also arise from the electrostatic interactions of the electrons?

  Contact
• An _ will have not external forces
• An _ will have not external forces?

  Isolated system
• The principle of _ states when no external forces act on a system consisting of two objects that collide with each other, the total momentum remains constant in time?

  Conservation of momentum
• The total momentum before the collision will _ the total momentum after the collision?

  equal
• _ are also equal and opposite?

  Impulses
• _ is conserved for the system of objects?

  Momentum
• _ is conserved in any collision?

  Momentum
• _ kinetic energy is not conserved?

  Inelastic collisions
• _ some of the kinetic energy is converted into other types of energy such as heat, sound?

  Inelastic collisions
• _ occur when the objects stick together?

  Perfectly inelastic collisions
• Both momentum and kinetic energy are conserved?

  Elastic collision
• Most collision fall between elastic and perfectly inelastic collisions?

  Actual collisions
• Momentum is a _ which direction is important?

  Vector quantity
• In a _, momentum is conserved, kinetic energy is not, two objects stick together, so their final velocities are the same?

  Perfectly inelastic collision