How Fast is it?

Question

What is the 0-60 mph time for a falling rock, person, whatever. And how many feet would it take? So basically; A Falling Acceleration and Distance question.

OK, Im not a mathmatician, thats why Im asking you all. Your answer should look like this .. "It would be 2.1 second 0-60 and it would take 30 feet" But with the proper numbers, I just guessed. Tanks!

Answer 1

The time is v/g = 2.735 sec
The distance is .5*g*t^2 = 120.345 ft

Answer 2

Characteristic of a fall is Acceleration is constant, that is, according to F=m.G where F is the pull of gravity (weight) and G is acceleration.
Acceleration is equal to Distance x derived 2 times , and is also equal to Speed v derived one time ( since Speed is the first derivative of distance x)

So, d²x/dt² = G
Speed v = dx/dt = G.t + v0 ( if v0 is the initial velocity)
Distance x = (1/2).G.t² + v0.t + x0 ( if x0 is the initial distance/height at the start of the clock.

We will assume that at start the rock is at rest ( v0=0) and all heights are measured downwards from origin zero ( x0=0)

A rock/person will reach 60 mph = 26.7 meters per seconds
in t=v/G = 26/9.8 = 2.72 seconds
It would fall x= (1/2)*(9.8)*(2.72)² = 36.28 meters

Answer 3

It would be a 2.72 second 0-60 mph time and it would be in 119 feet.

Answer 4

ok...so im used to do this in metric units, lets say that 60mph=100km/h

u=0
v=100
a=10
t=10......just divide v with a...
therefore from:
v2=u2+2as
10sq.=2[10][s]
100=20s
s=5 metres
so the answer would be approx. 5m/3=5 feet
if this didnt help you just try following the method and put your units in