A baseball player friend of yours wants to determine his pitching speed. You have him stand on a ledge and throw the ball horizontally from an elevation 5.0 mm above the ground. The ball lands 20 mm away. What is his pitching speed?

Explanation:

Data provided in the question:

Height above the ground, H= 5.0m

Range of the ball, R= 20 m

Initial horizontal velocity =

Initial vertical velocity=  (Since ball was thrown horizontally only)

Acceleration acting horizontally, = 0 m/s²  [ Since no acceleration acts horizontally) ]

Vertical Acceleration, = 9.8 m/s² (Since only gravity acts on it)

Let 't' be the time taken to reach ground

Therefore, using equations of motion, we have

Then using Equations of motion for horizontal motion,

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