Posted by Andy on .
A ball is thrown upward from a platform 5.1 meters high with a speed of 13 m/s at an angle 45 degrees from the horizontal. what is the magnitude of its velocity when it hits the ground?

physics 
drwls,
No matter what the angle is, the ball will gain kinetic energy M g H, the potential energy decrease. The kinetic energy per mass is V^2/2.
Therefore V^2 will increase by 2gH, from 169 m^2/s^2 to 169 + 2*9.8*5.1 = 269 m^2/s^2.
The new velocity = 16.4 m/s