how long does it take a car to accelerate from 3.4m/s to 20.9m/s if the average acceleration is 6.0m/s (squared).

Physics

1 answer:

Gre4nikov [31]3 years ago

4 0

Average acceleration is the ratio of the change in velocity to the time it takes for that change to occur:

$a_{\mathrm{av}}=\dfrac{\Delta v}{\Delta t}$

We want to find $\Delta t$ :

$6.0\,\dfrac{\mathrm m}{\mathrm s^2}=\dfrac{20.9\,\frac{\mathrm m}{\mathrm s}-3.4\,\frac{\mathrm m}{\mathrm s}}{\Delta t}$

$\implies\Delta t=2.9\,\mathrm s$

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