3 years ago

A ball is dropped from a height of 20 meters. At what height does the ball have a velocity of 10 meters/second?

Physics

1 answer:

borishaifa [10]3 years ago

6 0

Answer:B

Explanation:

Initial velocity, u=0m/s

Distance,s=20m

a=+g=9.8m/s*s

Using v*v=u*u+2gs

v*v=0+2*9.8*20

v*v=392

v=19.8

When s=20m, v = 19.8m/s

Therefore when v = 10m/s, s= 10*20/19.8

s =10.1m

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