Who knows something about physics?

I am sooooo stuck on an apparently simple physics questionSay an object starts at rest and travels 400m in 20s what is the acceleration.
I tried google, half an hour and no answer or formula, little help?

any top speed limit? is the acceleration linear?

Acceleration is uniform, Initial velocity is 0
Average speed is 20m/sThats ALL the info I gotKedit:: Trial and error proved Final speed to be 40m/s and acceleration to be 2m/s/s... Now can anyone provide a simple formula so I can show working out?

v = d/t

But I need the acceleration, not speedah, dont worry, I'll just "forget" the working out for this one, thanks anyway guys

yeah...i took physics class for 2 years...and HATED every single minute of it. I guess i don't have enough processing power :Dto answer your question...you better ask someone else :D

Sorry I'm a bit late, had some other stuff to do, also needed to look up the formulas again since it's been ages since I've done this.legend:
Δ = delta = the difference (final - initial)Since you know the distance and not the acceleration we should use the distance formula first to find the final velocity.d = 1/2 * Δv * ΔtFill in what we know400 = 1/2 * v - 0* 20 - 0
400 = (1/2) * v - 0 * 20Rearrange it to have velocity by itself.
v = 400 / ((1/2) * 20)// and finally solve it. (400 divided by half of 20)
v = 40Thus the final velocity is 40 metres per second.You then need to find the acceleration, for this you need the following formulaa = Δv/ΔtFill in what we know
a = 40 - 0 / 20 - 0
a = 40 / 20
a = 2Thus the acceleration rate is 2 metres per second increase per second.

acceleration should be written as metres/second squared.

if you suppose acceleration to be linear there is a simple formula s=(1/2)at^2+vt
Where
s: the distance covered
a: acceleration
t: time
v: initial velocity(which here is 0)
that makes 400=1/2*a*20*20
then a=2