## Distance Travelled Over Time

Hi, all

I have a question that I've been Googling for the past hour or so, and cannot find the answer to. I seem to remember it has something to do with the logarithmic scale. I hope somebody here can answer it for me:

A car accelerates from 0 to 60km/h in 4.2 seconds. What I'd like to know is how far the car has travelled (In metres) after the 4.2 seconds - when it has attained its 60km/h speed.

We cannot assume a constant acceleration, as the speed increases gradually every second of the 4.2 seconds.

Can anybody help with this?

Cheers
Nocturne

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 Mentor Blog Entries: 9 If we do not assume contant and do not have the rate of acceleration as a function of time there is not a unique answer to the question. The distance traveled is determined by the rate of acceleration. Assuming a contant acceleration you can use: $$x = \frac 1 2 a t^2$$ with $$a = \frac { \Delta v } { \Delta t} = \frac {60 km/h} {4.2 s}$$ You will need to convert the 4.2 seconds to hours.
 Mentor You need to know what the acceleration of the car looks like, and that isn't that easy to find without making some pretty big assumptions.