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mugzieee
Feb14-05, 07:51 PM
David is driving a steady 31.0m/s when he passes Tina, who is sitting in her car at rest. Tina begins to accelerate at a steady 2.30m/s^2 at the instant when David passes.

How far does Tina drive before passing David?
What is her speed as she passes him?

i tried doing an integral for this problem but can find the limits

StatusX
Feb14-05, 07:54 PM
Just do an indefinite integral and set the constant c so that it fits your initial conditions.

hypermorphism
Feb14-05, 07:56 PM
There is no need to integrate if you already know the kinematic equations for the position of an object in uniform velocity and the position of an object in uniform acceleration. You know that Tina and Dave start from the same position at some time t. Make that position the origin (0) and let that time be t=0. All you have to do now is set the positions of Tina and Dave equal to each other to see what time Tina passes Dave. Using that time in standard kinematic equations, you can go back and answer both questions about Tina.

mugzieee
Feb14-05, 07:57 PM
what would i set c to? 31?

StatusX
Feb14-05, 08:03 PM
If t=0 is where they pass, and you get an equation for v(t) with a C in it, just plug in 0 for t, set v(0) to the initial velocity, and solve for C. I don't know the exact equation you have, so I can't tell you what to set C to.