An object is dropped from a platform 100 feet high. Ignoring wind resistance, what will its speed be when it reaches the ground?

2 answers:

7 0

if we assume the origin is at the dropping point and the object is merely dropped and not thrown up or down then y0 = 0 and v0 = 0. The equation reduces to 

y = 0 + 0t + ½gt² 
y = ½gt² 

t = √(2y/g) 

in the ft - lb - s system 

y = -100 ft 
g = -32.2 ft / s² 

t = √(2y/g) 
t = √(2(-100) / (-32.2)) 
t = 2.5 s

Irina-Kira [14]3 years ago

4 0

the answer to the question is 2.5

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