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A spring of spring constant 800 N/m is used to launch a 15.0 g projectile vertically upward.  By how much must the spring be compressed in order for the projectile to reach a maximum height of 35.0 m?

A child sleds down a 3.5 m tall snowy hill.  Ignoring friction, determine the child’s speed at the bottom of the hill.

A 500 kg ore cart traveling at 12.0 m/s on a level track is stopped by a spring of spring constant 35,000 N/m mounted horizontally at the end of the track.  By how much does the spring compress in stopping the car?

psoccer.png A 425 g soccer ball traveling horizontally along the ground at 15.0 m/s is kicked in the opposite direction by a player with a speed of 25.0 m/s at an angle of 60.00 up from the horizontal.  If the time of contact between the player and the ball for the kick was 0.025 s, what was the magnitude of the force exerted on the ball?

A 90.0 kg wide receiver traveling east at 15.0 m/s is tackled by a 115 kg linebacker traveling at 8.0 m/s in a direction of 300 west of north.  What are the speeds of the players (assume they stick together) just after the tackle?

A rocket expels 1500 kg/s of propellant at a speed of 4.00×104 m/s.  Determine the force on the rocket.

A 9.0 kg mass lies along the y-direction a distance of 4.0 m from the origin, and a 6.0 kg mass lies along the x-direction a distance of 3.0 m from the origin.  Determine the distance from the origin to the center of mass.

Three masses lie along the x-direction.  A mass M is at the origin, a mass 2M is at x = a, and a mass 3M is at position x = 2a.  Determine the position of the center of mass relative to the origin.

p6(3).png For the above molecule, M = 16m, d = 1.0 Å (Å = 10-10 m), and the center of mass lies 0.067 Å from the M mass atom.  Determine the angle q for the molecule.

A  5.00 kg object traveling East at 12.0 m/s undergoes a perfectly inelastic collision with a 3.00 kg object traveling West at 10.0 m/s.  Determine the velocity to the center of mass before and after the collision to show it is constant.