How Long Until You Reach the Curve at 180.7 km/hr?

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Traveling at 180.7 km/hr and covering 0.5 km until reaching a curve results in approximately 9.936 seconds until the curve is reached. The calculation involves dividing the distance by speed, yielding a time of 0.00276 hours. However, the precision of the answer is questioned due to significant figures; the distance is only given to one significant figure, while the speed is more precise. Therefore, the final answer should reflect the least precise measurement, which is one significant figure. The discussion highlights the importance of considering significant figures in calculations.
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Homework Statement


Traveling at a speed of 180.7 km/hr, you only have about 1/2 km until you reach the curve. At this speed, how many seconds do you have until you reach the curve? Don't forget to convert your answer to the correct units.

Homework Equations


t = d/v ??

The Attempt at a Solution


.5km / 180.7km/hr the km's cancel out and the result is 0.00276 hr

To convert to the units, taking 3600 seconds and multiply by 0.00276 = 9.936 seconds to reach the curve.

Is this correct?

Thank you,
z28
 
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This is correct-ish.

Does your teacher care about "significant figures" (aka "sig figs")?

Because the speed is given to four digits, but the distance given is only "about 1/2 km" which is only a single sig fig. That means your answer, which is precise to the thousandth of a second, contains too many digits to be of any use.
 
Oh, yes, I see. Thank you
 
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