Physics
posted by Lost In Studies on .
There are two wheels with diameter 30 inches and 20 inches. The first wheel covers a certain distance in 240 revolutions. In how many revoluions would the second wheel cover the same distance?

dwould it be proportional? The linear distances their circumferences are in a set proportion.
30/240=20/N 
bobpursley,
Thanks for your responce and help, I don't think so it's proportional. Since the answer is 360 revolutions.
And putting them in proportions doesn't give the correct answer.
A friend told me this solution;
Find the circumference of both the wheels by formula 2 pi r:
1st wheel: 94.2 inches.
2nd wheel: 62.8 inches.
Now multiply the circumference of the 1st wheel by revolutions:
94.2*240 = 22608 inches.
This would be the otal distance traveled by wheels.
Now divide the distance by the circumference of second wheel,
you'll get no. of revolutions:
No. of revolutions: 22608/62.8
No. of revolutions: 360 revolutions.