# Simple conversion

"A sprinter accelerates from rest to 10.0 m/s in 1.35 seconds. What is her acceleration in (a) m/s^2, and (b) km/h^2?"

I got (a) right. Acceleration = 10/1.35 = 7.41 m/s^2. But I somehow screw it up when I go to do the conversion. Here's what I did:

10 m = 0.01 km

1.35 s = 3.75 x 10^-4 hr (1.35 x (1 hr/3600 s)

So the sprinter accelerated 0.01 km in 0.000375 hrs.

But 0.01 km/0.000375 hr = 26.67 km/hr^2, and the answer is supposed to be 9.60 x 10^4.

What am I doing wrong here?

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#### Solution Preview

<br>Look at your solution:0.01 km/0.000375 hr = 26.67 km/hr^2

<br>km/hr you are equating as km/hr^2

<br>solve ...

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