Determinging Acceleration and Distance

[C42711]

If a rocket-powered sled is accelerated to a speed of 444 m/s in 1.8s, then what is the distance that the sled travels?

So, my given:
v_f= 444 m/s
t= 1.8 s

I don 't know what equation to use to find distance. I tried:
d=v_i+1/2*at² , but that didn't work. I just really don't know what equation to use. The answer should be 400m. Any help would be much appreciated.

 

[Delphi51]

Knowing only the time and velocities, you must use a formula that has only three quantities - and use it to find the 3rd one. Ideally, you would use a constant accelerated motion formula with d,t,Vi, and Vf. If you can't find that one, use one to find the acceleration and then use d=vi+1/2*at2 to find the distance.

There must be a list of constant accelerated motion formulas in your textbook.
The classic version is here: http://en.wikipedia.org/wiki/Equations_of_motion#Equations_of_uniformly_accelerated_linear_motion

 

[PotentialE]

have yo tried A = (Vf - Vi) / T?
once you have the acceleration value, the distance formula should work just fine

 

[netgypsy]

Most of the time a sled would be accelerated from rest. If it isn't, it tells you the initial velocity.

 

[marcoskids]

Need to find acceleration first and then plug its value into the correct equation that you stated.

a = (v-u)/t = (444-0)/1.8 = 247m/s^2

d = vi+1/2*at2

= 0 + 1/2*247*1.8^2

= 400m