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TheShapeOfTime
Sep29-04, 03:26 PM
How do I switch the following formula for time?

delta d = Vi * delta t + 1/2 * a * delta t^2


d = distance
Vi = initial velocity
a = acceleration
t = time


Any sort of steps would be greatly appreciated as I don't just want the answer, I always like to know how it's done :).

P.S. Sorry about the wording of the question and how the formula is written out, I need to get better at it.

arildno
Sep29-04, 03:33 PM
What are the roots of a quadratic equation..?

TheShapeOfTime
Sep29-04, 03:59 PM
What are the roots of a quadratic equation..?

Sorry, but I don't really get what you mean (noobness :\). All I can tell you is that I know you solve quadratic equations by factoring.

EDIT: I removed my nonsense ;)

arildno
Sep29-04, 04:15 PM
You know how to solve for x the following equation, right?:
ax^2+bx+c=0 (a,b,c constants)

TheShapeOfTime
Sep29-04, 04:23 PM
You know how to solve for x the following equation, right?:
ax^2+bx+c=0 (a,b,c constants)


Looks like you replied while I was editing my post. My answer is yes.

arildno
Sep29-04, 04:40 PM
It seems you have severe problems with simple algebra (your edit is sheer nonsense).
Now, in order to proceed, try to rewrite your original equation into a form:
K_{1}(\delta{t})^{2}+K_{2}(\delta{t})+K_{3}=0
where K_{1},K_{2},K_{3} are constants (identify them!)
(\delta{t} is "delta t")

TheShapeOfTime
Sep29-04, 05:10 PM
It seems you have severe problems with simple algebra (your edit is sheer nonsense).
Now, in order to proceed, try to rewrite your original equation into a form:
K_{1}(\delta{t})^{2}+K_{2}(\delta{t})+K_{3}=0
where K_{1},K_{2},K_{3} are constants (identify them!)
(\delta{t} is "delta t")


K_{1} = 1/2a, K_{2} = Vf, K_{3} = d


Also, wouldn't it be -K_{3}, or am I wrong?

arildno
Sep30-04, 10:19 AM
What's wrong with setting:
K_{3}=-\delta{d}
Now, you should be able to determine which values \delta{t}
Choose the root which is makes sense physically.

TheShapeOfTime
Sep30-04, 05:19 PM
I understand now, thanks for helping me out!