# FORCE AND MOMENTUM

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• Created by: leighx
• Created on: 12-03-14 09:46
• FORCE AND MOMENTUM
• MOMENTUM
• momentum,p = mass * velocity, p=mv
• units =Kgm/s or Ns
• vector quantity
• direction is the same as the direction of velocity
• NEWTON'S LAWS OF MOTION
• 1: An object remains at rest or in uniform motion unless accelerated by a force.
• 2: The rate of change of momentum of an object is proportional to the resultant force on it. In other words, the resultant force is proportional to the change of momentum per second.
• 3: When two objects interact, they exert equal and opposite forces on each other.
• IMPULSE
• F = (mv-mu)/t
• F = m(v-u)/t
• a = (v-u)/t
• F = ma
• Impulse is the change in momentum
• Impulse = Fdt = d(mv)
• FORCE - TIME GRAPHS
• the area under the line of a force - time graph represents the impulse of the force.
• http://tap.iop.org/ mechanics/ momentum/222/ page_46460.html
• IMPACT FORCES
• If initially stationary, F=mv2/t
• If initially moving, F=mv-mu/t
• REBOUND IMPACTS
• Before: p=mu After: p=-mv
• change in direction
• F=(-mv)-mu/t
• If no loss of speed, v=u
• F=-2mu/t
• If direction of contact is not perpendicular to the wall, dp=-2mucosx
• CONSERVATION OF MOMENTUM
• m1u1+m2u2 = m1v1+m2v2
• the principle of the conservation of momentum states that for a system of interacting objects, the total momentum remains constant, provided no external resultant forces acts on the system
• ELASTIC AND INELASTIC COLLISIONS
• FORCE AND MOMENTUM
• MOMENTUM
• momentum,p = mass * velocity, p=mv
• units =Kgm/s or Ns
• vector quantity
• direction is the same as the direction of velocity
• NEWTON'S LAWS OF MOTION
• 1: An object remains at rest or in uniform motion unless accelerated by a force.
• 2: The rate of change of momentum of an object is proportional to the resultant force on it. In other words, the resultant force is proportional to the change of momentum per second.
• 3: When two objects interact, they exert equal and opposite forces on each other.
• IMPULSE
• F = (mv-mu)/t
• F = m(v-u)/t
• a = (v-u)/t
• F = ma
• Impulse is the change in momentum
• Impulse = Fdt = d(mv)
• FORCE - TIME GRAPHS
• the area under the line of a force - time graph represents the impulse of the force.
• http://tap.iop.org/ mechanics/ momentum/222/ page_46460.html
• IMPACT FORCES
• If initially stationary, F=mv2/t
• If initially moving, F=mv-mu/t
• REBOUND IMPACTS
• Before: p=mu After: p=-mv
• change in direction
• F=(-mv)-mu/t
• If no loss of speed, v=u
• F=-2mu/t
• If direction of contact is not perpendicular to the wall, dp=-2mucosx
• CONSERVATION OF MOMENTUM
• m1u1+m2u2 = m1v1+m2v2
• the principle of the conservation of momentum states that for a system of interacting objects, the total momentum remains constant, provided no external resultant forces acts on the system
• An elastic collision is one where is no loss of kinetic energy
• A totally inelastic collision is one where the colliding objects stick together
• A partially inelastic collision is one where the colliding objects move apart and have less energy after the collision than before