A 28000-kg open railroad car, initially coasting at 0.775 m/s with negligible friction, passes under a hopper that dumps 110000 kg of scrap metal into it.

A 107.5-kg rugby player is initially running at 8.5 m/s in the positive direction, but collides head-on with a padded goalpost and experiences a backward force of 1.72 × 104 N for 5.45 × 10–2 s.a, Calculate the final velocity in the horizontal direction of the rugby player, in meters per second.

Squid rely on jet propulsion when a rapid escape is necessary. A 1.5 kg squid at rest pulls 0.10 kg of water into its mantle, then ejects this water at a remarkable 45 m/s. Right after this ejection, how fast is the squid moving?

A 0.15 kg baseball is moving at 35 m/s toward home plate when it is hit with the bat. The ball is in contact with the bat for 0.0019 s, and leaves the bat at 25 m/s directly away from home plate. Determine the average force exerted by the bat on the ball.

A 46.0-kg skater is traveling due east at a speed of 2.60 m/s. A 66.0-kg skater is moving due south at a speed of 6.10 m/s. They collide and hold on to each other after the collision, managing to move off at an angle  south of east, with a speed of vf. Find (a) the angle  and (b) the speed vf, assuming that friction can be ignored.

What is the acceleration of a 5000 kg rocket taking off from the Moon, where the acceleration due to gravity is only 1.6 m/s^2 if the rocket expels 8.00 kg of propellant per second at an exhaust velocity of 2.20 × 10^3 m/s?

A 5427.28 kg open train car is rolling on frictionless rails at 25.15 m/s when it starts pouring rain. A few minutes later, the car's speed is 15.38 m/s. What mass of water has collected in the car?

A 0.53 kg billiard ball initially at rest is given a speed of 14 m/s during a time interval of 5.0 ms . What average force acted on the ball during this time?

Cuttlefish use jet propulsion to move rapidly. To do this, a cuttlefish fills its muscular mantle cavity with water and then quickly expels the water through a tube-like opening. The mass of a cuttlefish is about the same as the mass of water of the same volume. A 14-cm-long and 6.0-cm-wide cuttlefish, initially at rest, is moving at a speed of 4.0 m/sm/s after expelling the water from its body. Assume that the cuttlefish has a cylindrical form, the mantle cavity has a form of a cylinder with a length of 9.0 cm, and the thickness of the muscle surrounding the sides of the cavity is 1.0 cm. Estimate the speed of the expelled water relative to the sea bed. Express your answer with the appropriate units.

A diver with a mass of 80 kg jumps from a dock into a 130 kg boat at rest on the west side of the dock.  If the velocity of the diver is 4.1 m/s to the west, what is the final velocity of the diver in the boat?