# Determining distance from velocity, acceleration, and time.?

A rocket sled accelerates at 28.5 m/s^2 for 9.00 s . v = 257 m/s

How far has it traveled?

i have tried d = vt and d = vt + (1/2)at^2 but neither of these work

any help is appreciated

### 4 Answers

- SteveLv 77 years agoFavorite Answer
Since d = vt is for non-accelerating situations, it is clearly of no use here.

Your second formula should read: d = Vi*t + ½a*t² where Vi is the initial velocity.

In your problem, Vi = 0, so that entire term drops out, leaving

d = ½a*t² = ½*28.5*9² = 1154.25 m

v = 257 m/s = final velocity = a*t

Note that this velocity is not used to compute the distance......

- Randy PLv 77 years ago
Don't apply formulas randomly. Know what they mean.

d = vt is for constant velocity.

d = vt + (1/2)at^2 is for uniform acceleration, which this is.

a = acceleration

t = time

v = INITIAL velocity. Was that the initial velocity or the final velocity? If it was the final velocity, you're going to need one more equation to find the initial velocity, such as this: a = (change in v)/time, or vf = vi + at

- 7 years ago
Remember that Velocity is equal to distance x time which is meters per second. So, the distance travelled is equal to 257m/s divided by 9.00 seconds. When you divide it, the answer should be 28.556 meters. Hope it helps!

- 7 years ago
this is right

d = vt + (1/2)at <(to the second power)

you should get:

662.625

hope i helped! i think that this is right... but if im wrong, sue me