A pendulum is made of a 250 g metal ball suspended 50.0 cm below a support by a string. The ball is moved sideways along the swing arc so that it is 3.0 cm higher than it is at the bottom of its swing. The ball is then released.

Calculate the speed of the ball at the bottom of the swing.

I feel like i understand this question, but at the same time i'm a little lost. An explanation on how to solve this would be greatly appreciated- but please dont give me the actual answer as id like to try it myself! Thanks :)

Respuesta :

AL2006
That's the spirit ! You can do this! When the ball is 3 centimeters high it has gravitational potential energy. The potential energy is mass times gravity times height. The height is .03 meter. When it gets to the bottom all that potential energy is changed to kinetic energy. The kinetic energy is 1/2 times mass times speed squared. There you have it. 1/2 mass times speed squared equals mass times gravity times .03 centimeters. The only thing you don't know in that equation is the speed and you can solve the equation to find it. Now go gettum ! !