Physics question...stumped I am...been working for an hour...This time its hard!

[kmart64]

A 1000 kg weather rocket is launched straight up. The rocket motor provides a constant acceleration for 19 s, then the motor stops. The rocket altitude 23 s after launch is 5200 m. You can ignore any effects of air resistance.

What was the rocket's acceleration during the first 19 s?

What is the rocket's speed as it passes through a cloud 5200 m above the ground?

So far, I am always left with 2 variables when kinematic equations are used...god mechanical engineering ;P

[kmart64]

oh man, I got it...sick finally...for those that are wondering its 20.5786 for part a...

[Phempa]

phew, thank god....

I wouldn't have be able to go on with life

[ACC0RD22]

oh man, I got it...sick finally...for those that are wondering its 20.5786 for part a...

20.5786 WHAT??

you wouldnt even get credit if you left your answer like that in my physics class. we get points for just getting the right units, even if the answer is way wrong (and the way we got the units is totally off). we dont get MANY points for that, but we do get some points for making sure we ahve the right units, even if they dont make sense.

I have a physics test tommorow. totally not looking forward to it.

F = (kqq)/(r^2) <<the most important equation thats come up in my class yet.

LOTS of interesting stuff can be taken from it.

like

E = (kq)/(r^2) <-- how to find the E-field (of a point charge)

or V = (kq)/r <-- how to find the electric potential (of a point charge)

or gauss' law

ε.0*Φ=q.enc

Im totally NOT trying to put off studying, I swear.

did you say you were in engineering?

if so, learn those equations, youll need them when you take electricity and magnetism.

EDIT: also, if youre left with 2 variables, use all of your equations. theres 5 of them for a reason. find the value of one of the variables with one of the equations that is "missing" one of the variables you dont have.