A400.0 kg storage box is held 10 m above ground by a forklift. what is its gravitational potential energy? (pe = mgh) a) 410 j b) 3920 j c) 4000 j d) 39,200 j

D.) 39,200 J

Via the equation of potential energy PE = mgh where m is mass, g is the average gravity on earth and h is the height.  In this case m = 400 kg, g = 9.8, h = 10 m thus:

P.E.= 39,200 Joules

12000j is work done

the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.