Posted by **Tarra** on Thursday, February 2, 2012 at 11:35pm.

A ball is thrown straight up and rises to a maximum height of 20 m above the ground. At what height is the speed of the ball equal to half of its initial value? Assume that the ball starts at a height of 2.1 m above the ground.

- Physics -
**drwls**, Friday, February 3, 2012 at 8:28am
When the speed is 1/2 of the initial value, 1/4 of the initial kinetic energy will be lost to potential energy, and the ball will be at 3/4 of its maximum distance above where it was thrown from. It rises a total of 17.9 m. 3/4 of that is 14.43 m. Add that to 2.1 m for the answer.

## Answer this Question

## Related Questions

- Physics - A ball is thrown straight up and rises to a maximum height of 24 m ...
- Physics - A ball is thrown straight up and rises to a maximum height of 21 m ...
- Physics - Can you help me through this one? I don't want just the answer: A ball...
- Physics - A ball is thrown straight upward and rises to a maximum height of 20 m...
- Physics - A ball is thrown straight upward and rises to a maximum height of 23 m...
- physics - A ball is thrown straight upward and rises to a maximum height of 14.6...
- Physics - A ball is thrown straight upward and rises to a maximum height of 16 m...
- Physics - A red ball is thrown down with an initial speed of 1.3 m/s from a ...
- physics - A red ball is thrown down with an initial speed of 1.2 m/s from a ...
- phy - A blue ball is thrown upward with an initial speed of 20.6 m/s, from a ...