SOLUTION: Well it's about physics. The topic is ENERGY. Can you please help me answer this problem? A 15 kg child sits in a swing that is attached to ropes 1.6 m long. Find the potential en

Algebra ->  Test  -> Lessons -> SOLUTION: Well it's about physics. The topic is ENERGY. Can you please help me answer this problem? A 15 kg child sits in a swing that is attached to ropes 1.6 m long. Find the potential en      Log On


   



Question 210331: Well it's about physics. The topic is ENERGY. Can you please help me answer this problem?
A 15 kg child sits in a swing that is attached to ropes 1.6 m long. Find the potential energy of the child relative to his lowest position when the ropes (a) are horizontal, (b) are vertical, and (c) make 30 degrees with the horizontal.
Thank you very much..

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the potential energy (in joules) is the mass (in kg), multiplied by the height difference (in meters), multiplied by the gravitational acceleration (g)

PE = mgh

(a) for a horizontal rope ___ PE = 15 * 9.81 * 1.6

(b) when the ropes are vertical, the child is at the lowest position

(c) at a 30º angle to the horizontal, the height is half the rope length ___ PE = 15 * 9.81 * .8