The expression for gravitational potential energy is “-(G*M)/r”. a) True b) False

18. What is the gravitational potential energy of a 70 kg person standing on the roof of a 12-story building relative to (a) the tenth floor, (b) the sixth floor, (c) the first floor? (Each story is 2.80 m high.)

Problem 2: A certain spring has a spring constant k₁ = 660 N/m as the spring is stretched from x = 0 to x1 = 35 cm. The spring constant then changes to k₂ = 250 N/m as the spring is stretched to x2= 65 cm. From x₂= 65 cm to x3 = 89 cm the spring force is constant at F3 = 105 N.

"Energy per unit time" is a quantity called Power.  Which of the following combinations has the same units as power? A   length squared times mass over time squared B   persimmons. C   speed times mass times acceleration over time D   Force times acceleration E   {potential energy minus kinetic energy} times time F   Force times velocity G   speed squared times mass H   mass time acceleration I   mass squared times acceleration.