the drive wheel of a car is 38 inches in a diameter . how many times will it turn over a distance of 1km.?

Question

compphysgeek · Answer

again you need the conversion factor from inches to meter. if you've got that you can calculate the circumference of the wheel in meters. Once you know that you can divide 1000 m by the circumference and you'll get the number of turns

anonymous · Answer

How many πD s are there in 1km 
1 inch = 0.0254m 
38 inch = 0.9652 m 
πD = 0.9652π 
1km = 1000m 
N = 1000 / 0.9652π = 330 revolutions.

anonymous · Answer

correct?

compphysgeek · Answer

that's correct

anonymous · Answer

any solution that  can i cancel out?

compphysgeek · Answer

you've got the first step $$ 38 in \times \frac{0.0254 m}{1 in} $$ I dont see anything else where you can cancel anything out

compphysgeek · Answer

ok .. the last step of course $$ \frac{1000 m}{0.9652 m \times \pi} $$ that gives you a number without any units

anonymous · Answer

329.7864...

compphysgeek · Answer

yes, rounded 330 as you had before

anonymous · Answer

what is km?

compphysgeek · Answer

what do you mean?

anonymous · Answer

330 is distance?

compphysgeek · Answer

no, 330 is the number of revolutions. It doesn't have a unit

anonymous · Answer

ah ok

compphysgeek · Answer

when we divided 1000m by $0.96xx m \times \pi$ the meters cancelled out.