(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An ice sled powered by a rocket engine starts from rest on a large frozen lake and accelerates at +11.0 m/s2. At t1 the rocket engine is shut down and the sled moves with constant velocity v until t2. The total distance traveled by the sled is 5.30x10^3 m and the total time is 81.0 s.

Find t1, t2, and v.

so,

a= +11.0 m/s^2

deltat= 81.0 s

deltax or d= 5300 m

t1= ?

t2= ?

v= ?

2. Relevant equations

well, i tried to use:

1. d= Vi*t + .5at^2

2. d= Vi + at^2

^ I'm not sure if those are right to use.

3. The attempt at a solution

Okay, well what I did first was this:

I used the first equation listed and put in everything I knew, which ended up with this:

d= 5.5t^2

Then, I used the second equation to also solve for d.

d= 11t

I know the entire distance is 5300m, so I then did:

5300= 5.5t^2 + 11t

however, i'm not exactly sure as to where i can use the deltat of 81.0s. I know that I'm going to have to use the quadratic forumla from here, but I don't know what to do. I was thinking of doing something like this:

5300= 5.5t^2 + 11t (81-t)

But, I'm not sure that is accurate.

I'm stuck right now as of what to do. Help would be muchh appreciated. Thanks!

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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