Mike then takes his now 1175 kg car and crashes it at 50 m/s into the back of a 1600 kg Jeep traveling at 10 m/s.  They roll off together going 18 m/s.  How much work was done by the crumple zone of Mike’s car?

A 6.30-kg object is initially moving so that its x-component of velocity is 6.00 m/s and y-component of velocity is -1.60 m/s. (a) What is the kinetic energy of the object at this time? (b) Find the change in kinetic energy of the object it its velocity changes so that its new x-component is 8.50 m/s and its new y-component is 5.00 m/s.

A 4 kg block moving right at 6 m/s collides elastically with a 2 kg block moving right at 3 m/s. Calculate the final kinetic energy. What is the velocity of a 10 kg object move if an average power of 120 watts is used and the applied force is parallel to the surface? 1.22 m/s 12.2 m/s 0.82 m/s 102 m/s 82 m/s

Two blocks are free to slide along the frictionless wooden track as shown in the figure.  The block of mass m1 = 5 kg is released from rest from the position shown, at height h = 5.00 meters above the flat part of the track.  At the bottom of the track rests mass m2 = 10 kg.   No work is done by non-conservative forces     a.What is the speed of block m1 just as it reaches but before it collides with block m2 (use Cons. Of Energy)?   b.What is the velocity of m1 just after it collides elastically with m2 (use Conservation of Momentum)?            and what is the velocity of m2 just after it collides elastically with m1 (use Conservation of Momentum)?   c. How far back up the ramp does m1 rise after the collision (use Cons. Of Energy?) and also find that if an 7 kg block, m3, that lies to the right of m2, is moving toward m2 (after m2’s collision with m1) at a speed of 26.8 mph (conversion!), what is the velocity of the m2/m3 couple after they collide in a perfectly inelastic collision…