Answers (cont.)
n 2.) Since position #2 is half
way down total energy will be
half in PE and half in KE
n So…KE at position #2 will be
half that at position #3
n So…KE at position #2 is
78.125J
n Then use KE (at #2)=78.125J
=1/2 x 0.5kg x v2
n v=17.68m/s at position #2