No slip wheel, distance covered, find revolutions

AI Thread Summary
The problem involves calculating the number of revolutions a bicycle wheel makes when traveling 3.0 km with a wheel radius of 0.400 m. The formula used is the distance divided by the circumference of the wheel, calculated as 2πr. The calculation yields approximately 119.4 revolutions, but this result does not match any of the provided answer options. Participants express confusion over the discrepancy and note that revolutions should not be measured in meters, indicating a misunderstanding in the initial calculations. The discussion highlights the importance of clear unit conversions and accurate calculations in solving such problems.
jehan4141
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The radius of each wheel on a bicycle is 0.400 m. The bicycle travels a distance of 3.0 km. Assuming that the wheels do not slip, how many revolutions does each wheel make?

This problem seems so simple but none of the possible answers available seems correct.

My work

r = 0.4 m
x = 3 km = 3000 m

# of revolutions = x / [(2)(Pi)(r)] = 3000 / (2 x 3.14 x 0.4) ~119.4 m?

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Below are the answers to choose from

8.4 × 10-4 revolutions


1.2 × 103 revolutions


Since the time of travel is not given, there is not enough information for a solution.


6.0 × 103 revolutions


2.4 × 102 revolutions
 
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I think you slipped a decimal place in your calculation. Also, revolutions are not measured in units of meters.
 
that is the weirdest thing. i think i calculated that about 4 times before getting frustrated and posting here. thank you so much!
 
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