1 Throwing a 3 kg hand grenade off a platform 40 m off the ground, with vx = 10m/s. Two seconds later a 2 kg piece hits the ground 10 m from the base of the platform. Where is the 1 kg piece at that time? Remember that Momentum is a Vector! A car (m=1000kg, v =40m/s) collides at right angles with similar car going at 30m/s. They stick together. What is their speed afterwards? A 2 kg mass travelling at 1 m/s slides into a stationary 2 kg mass. They stick together. Much kinetic energy is lost? If the collision is elastic, then no kinetic energy is lost – what solution is there that conserves both K and p? Newton”s Collision Balls – an example of an elastic collision. General case of a 2-body collision. Equations to find final velocities are given on p 222. These will be given on the formula sheet for the test. Special cases of these equations – what if m1 = m2? What if m2 >> m1 and v2i = 0? What if m2 >> m1 and v2i = -v1i?