Harry and hagrid needed to get money out of gringotts bank. the bank cart was accelerating at a rate of 4 m/s2 and it had a mass of 8,000 kg. what is the net force acting on the cart? use the formula: f=m∙a show all your work!

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.