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Washable_Marker
Sep25-05, 08:08 PM
Hello, thanks for reading =)

Let's just jump into it...
At the instant the light turns green, a car accelerates from rest at a rate of 1.8m/s^2. A truck gets to the intersection by the time the light changes [and therefore doesn't have to stop]. The truck is travelling at a constant velocity of 8.5m/s.

What will be the displacement of the car [assuming the intersection is 0] when it passes the truck, and at what time will this occur?

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I've been trying to solve it by using a displacement-time graph, but obviously the car will have a curved graph, and I can't figure out the equation of it's line. Any tips on how to go about this, as well as tips to solve the question would be great.

Thanks!

Atomos
Sep25-05, 08:10 PM
you will find this formula useful:
d = v_i t + 1/2at^2

Washable_Marker
Sep25-05, 08:26 PM
Aha! Just what I was looking for, and thanks for not giving me the answer outright, it made it much more rewarding to get the right answer.

Thanks again!

Jameson
Sep25-05, 08:28 PM
Did you get the right answer? And I'm glad you appreciate when people don't just give away the solution. :)

Washable_Marker
Sep26-05, 05:15 AM
Yep, got it. That was all I needed for it to click in my brain.