SOLUTION: falling objects drop with an average acceleration of 9.8 m/s2.If an object falls from a tall building, how long will it take before it reaches a speed of 72 m/s?

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Question 1149549: falling objects drop with an average acceleration of 9.8 m/s2.If an object falls from a tall building, how long will it take before it reaches a speed of 72 m/s?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

x = number of seconds
y = free-fall speed of object in meters per second (m/s)
y = 9.8*x since the approximate acceleration is 9.8 m/s^2, meaning that each second, the object is falling roughly 9.8 m/s faster

Plug in y = 72 and isolate x
y = 9.8x
72 = 9.8x
9.8x = 72
x = 72/9.8
x = 7.3469387755102 which is approximate
x = 7.3

It takes roughly 7.3 seconds for the object's falling speed to be 72 m/s.

Note: I rounded to one decimal place as the given value 9.8 is reported at one decimal place.