Question

A pear hangs in a tree at a height of 1.8 m. The pear has a mass of 0.2 kg. The pear falls out of the tree and lands on the ground. (Use correct units in all answers.)
a. How much gravitational potential energy does the pear have before it falls?

b. How much kinetic energy does the pear have when it reaches the ground?

c. How fast is the pear moving when it hits the ground?

Answer 1

a) PE=mgh=0.2*9.8*1.2=2.352 J

b) KE=PE=2.352 J

c) $v=\sqrt{\frac{2KE}{m}}=4.85$ m/s