A 1000 kg dragon is at rest sleeping in outer space. A 50 kg unicorn runs into the dragon with a velocity of 600 ms . The final velocity of the dragon is 40 ms . What is the final velocity of the unicorn?

Consider a small frictionless puck perched at the top of a fixed sphere of radius r. if the puck is given a tiny nudge so that it begins to slide down, through what vertical height will it descend before it leaves the surface of the sphere? [hint: use conservation of energy to find the puck's speed as a func e conservation of energy to find the puck's speed as a function of its height at what value of this normal force does the puck leave the sphere? ] here on the puck.