A railroad car of mass 2.7  104 kg moving at 4.50 m/s collides and couples with two coupled railroad cars, each of the same mass as the single car and moving in the same direction at 1.20 m/s. (a) What is the speed of the three coupled cars after the collision?  m/s (b) How much kinetic energy is lost in the collision?

2. A 0.600-kg particle has a speed of 2.00 m/s at point A and kinetic energy of 7.50 J at point B. What is (a) its kinetic energy at A? (b) its speed at B? (c) the total work done on the particle as it moves from A to B?

Р.2) A 45 kg rigid body is initially at rest at O on a frozen lake. Is it possible that once it has exploded into the three pieces, A, B, C, with masses ma = 20 kg, 15 kg, and mc = 10 kg, it can occupy the illustrated configuration rA/o = 50j m, rBlo = (30i + 20j) m, and = 70i m, at some later time? %3D MB %3D rcjo L. A j В

A system consists of three identical 13.32-lb particles A, B, and C. The velocities of the particles are, respectively, vA = vA j, vB = vBi, and vC = vCk. The angular momentum of the system about O expressed in ft·lb·s is HO = -1.2k.a) Determine the velocities of the particles. b) Determine the angular momentum of the system about its mass center G.

A raliway wagon A of mass 12 x 103 kg coasting at 1.2 m/s on a horizontal track crashes head-on and couples with a wagon B of mass 10 x 103 kg coasting at 1 m/s in the opposite direction, as shown in Figure 6. Determine: a) the common speed of the wagons just after collision assuming that the wheels are free to roll during collision%3B b) the average force between the two wagons, if the coupling takes place in 0.9 s. 1.2 m/s 1 m/s B

Three blocks (1,2,3) of mass 3.00 kg, 2.00 kg, 1.00 kg sit block 1 block 2 block 3 linearly 10.0 cm apart from each other on a frictionless surface. •> 3kg A 25 g bullet is shot at the first block, it travels through the first block, and embeds itself into the second block (without falling over) which then collides into the third block. a. Assuming the final collision is elastic, and the third block has a final velocity of 5.00 m/s, what is the velocity of block 2 just before it collides into block 3? b. What is the velocity of the bullet before it embeds itself into block 2? c. Assuming the bullet slowed down by only 10% while it travelled through block 1, what was the speed of block 1 after the bullet traveled through it?

Calculate the kinetic energy loss in a perfectly inelastic collision between an object of mass 40kg with velocity 8m/s and an object of mass 60kg coming in the opposite direction with velocity 2m/s.