Aweightlifter lifts a set of weights a distance of 2.00 m. if the weights have a mass of 60.0 kg and are pushed vertically upward at a constant speed, how much work is done on the weights?

The cement bag shown in the figure has a mass of 50 kg and the small pulley has a mass of 2 kg. if the cement bag is pulled upwards with an acceleration of 2 m/s^2, find the force f pulling the rope.

A500g object falls off a cliff and losers 100 j from its gravitational potential energy store. if the gravitational field strength g=9.8n/kg, how high is the cliff?

(a) assume the equation x = at^3 + bt describes the motion of a particular object, with x having the dimension of length and t having the dimension of time. determine the dimensions of the constants a and b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.) (b) determine the dimensions of the derivative dx/dt = 3at^2 + b. (use the following as necessary: l and t, where l is the unit of length and t is the unit of time.)