Question

The potential energy of an apple is 6.00 joules. The apple is 3.00-meters high. What is the mass of the apple?

Answer 1

                                         Potential energy  =  (mass) x (gravity) x (height)

Divide each side by (G x H) :      Mass  =  PE / (G x H) 

PE = 6 joules
Gravity = 9.8 m/s
Height = 3 m
                                                     Mass  =  6 / (9.8 x 3) =

                                                                     6 / (29.4)  =  0.204 kg
 
                                  (weighs about 2 newtons or 7.2 ounces on Earth)