(II) Car A hits car B (initially at rest and of equal mass) from behind while going 38 m/s Immediately after the collision, car B moves forward at 15 m/s and car A is at rest. What fraction of the initial kinetic energy is lost in the collision?

What is true about the total momentum before and after the collision?

A truck with a mass of 1480 kg and moving with a speed of 17.0 m/s rear-ends a 732 kg car stopped at an intersection. The collision is approximately elastic since the car is in neutral, the brakes are off, the metal bumpers line up well and do not get damaged. (a) Calculate the initial momentum of the truck (in kg m/s).  kg m/s (b) Calculate the final velocities (in m/s) for the truck and the car. vtf= m/svcf= m/s (c) Calculate the total momentum (in kg m/s) of the truck AND the car after the collision.  kg m/s (d) Did you expect the results that you got for Part (a) and (c)? Yes, since the collision is inelastic. No, since there were no forces acting on either the car or the truck during the collision.      Yes, since momentum is conserved in a collision with no external forces acting on the colliding objects. No, since kinetic energy may not be conserved.

A railroad car of mass M moving at a speed v 1 collides and couples with twocoupled railroad cars, each of the same mass M and movingin the same direction at a speed v 2. (a) What is the speed vf ofthe three coupled cars after the collision in terms of v 1 and v 2?(b) How much kinetic energy is lost in the collision? Answerin terms of M, v 1, and v 2.

A bumper car A (m. = 140 kg) with a velocity of 15 km/h hits a another car B (m = 160 kg) which was immobile before impact. The collision is perfectly elastic and the frictions are considered negligible.Calculate the time at which the dodgems are 2 m apart from each otherafter the collision.

None