1. Can potential energy be negative? Can kinetic energy? Can total mechanical energy? Explain

1. If the potential energy is zero at a given point, must the force also be zero at that point? Give an example.

1. How far would you have to stretch a spring with k=1.4 kN/m for it to store 210 J of energy?

1. A particle is trapped in a potential well described byU(x)=16x2b,withUin joules,xin meters, andb=4.0JFind the force on the particle when it's at (a)x=2.1m (b)x=0,and(c)x=1.4m