An athlete is running at a constant velocity with a javelin held in his right hand. the force he is applying on thejavelin as he carries it is 5.0newtons. if he covers a distance of 10 metrs, what work has he done on the javelin? .

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.