# physics

posted by .

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 -

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

## Similar Questions

1. ### physics

A ball is thrown from the top of a building upward at an angle of 66 ◦ to the horizontal and with an initial speed of 16 m/s. The ball is thrown at a height of 53 m above the ground and hits the ground 33.2074 m from the base …
2. ### physics

Three identical balls are thrown from a cliff of height, h, above a horizontal plane. One ball is thrown at an angle of 45 degrees above the horizon, the second is thrown horizontally, and the third is thrown at an angle of 30 degrees …
3. ### physics

Three identical balls are thrown from a cliff of height, h, above a horizontal plane. One ball is thrown at an angle of 45 degrees above the horizon, the second is thrown horizontally, and the third is thrown at an angle of 30 degrees …
4. ### physics

A ball is thrown upward from a platform 4.6 m high with a speed of 23 m/s at an angle of 40 o from the horizontal. What is the magnitude of its velocity when it hits the ground?
5. ### physics

A child throws a ball with an initial speed of 8 m/s at an angle of 40 degrees above the horizontal. The ball leaves her hand 1 m above the ground. How long is the ball in flight before it hits the ground?
6. ### physics

A ball is thrown upward from a platform 4.5 m high with a speed of 17 m/s at an angle of 41 o from the horizontal. What is the magnitude of its velocity when it hits the ground?
7. ### Physics

A ball is thrown upward from a platform 5.6 m high with a speed of 18 m/s at an angle of 35 o from the horizontal. What is the magnitude of its velocity when it hits the ground?
8. ### Physics

A grenade is thrown from a trench that is 10 meters below groud level. The soldier throws the grenade at a velocity of 30 m/s at an angle of 60 degrees above the horizontal. Determine the horizontal distance the grenade will fly before …
9. ### physics

A ball is thrown from a cliff upward with a speed of 20 m/s, the angle is 33 degrees and the ball hits the ground 9.2 seconds later, how high is the cliff to the nearest meter?
10. ### Physics

A golfer has to hit a ball over a tree that is 12.0 meters high from 40.0 meters away. The ball is hit with speed v at an angle (-) to the horizontal. Neglect any effect due to air. The golfer hits the ball with an initial velocity …

More Similar Questions