A ball is rolled off of a building that is 5m tall. Will the ball go over a wall that is 20m away and 2m tall? or will it hit the wall? Basically the question is how far from the ground will the ball be after traveling 20m.
V= 31.25 m/s
Show all work please.
2006-11-17 10:44:40 · 2 answers · asked by cloudykisses36 1 in Science & Mathematics ➔ Physics
Traveling at 31.25 m/s, the ball would reach 20 m in .64 seconds.
According to Galileo's free-fall, objects have a 9.81 acceleration.
So, in .64 seconds, the ball would have fallen 2.00704 m.
Subtract that from 5 m, you would get a number greater than 2 m, so I assume that if would clear the wall. I think.
(To Above) Isn't time equal to distance divided by velocity? For example, it travels at 31.25 m/s, so it would travel 31.25 meter in one second. Doesn't that go to say that 20 meter would take less than a second?
2006-11-17 11:17:29 · answer #1 · answered by Stev 1 · 0⤊ 0⤋
s = s0 + v0t + (1/2)at^2
2 = 5 - (1/2)(9.80662)t^2
t^2 = 2*3/9.80662
t = 0.7822
x = 31.25*0.7822
x = 39.95m, so the ball clears the wall.
Worked the other way,
t = 20/31.25
h = 5 - (1/2)(9.80662)(20/31.25)^2
h = 2.991,
so the ball clears the wall by almost 1 meter.
2006-11-17 19:30:20 · answer #2 · answered by Helmut 7 · 0⤊ 0⤋