A baseball is thrown straight downward with an initial speed of 40 ft=s from the top of the Washington Monu- ment (555 ft high).
1 answer:
Answer:
4.53 second, 195 ft/s
Explanation:
u = 50 ft/s
h = 555 ft
g = 32 ft/s^2
Let the time taken by the ball to reach the ground is t and the velocity of the ball as it hits the ground is v.
Use third equation of motion
v = 195 ft /s
Thus, the ball strikes the ground with velocity 195 ft/s.
Use first equation of motion
v = u + at
195 = 50 + 32 t
32 t = 145
t = 4.53 second
Thus, the ball reach the ground in 4.53 second.
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