Chapter A.2, Problem 46AYU

To determine

To find: How many revolutions will a circular disk with a diameter of 4 feet have completed after it has rolled 20 feet?

Answer to Problem 46AYU

One revolution.

Explanation of Solution

Circumference of the circle $C=\pi d=\pi \times 4=4\pi \text{ft}$.

Number of revolution $=$ Total rolled$/$circumference of the disk.

Number of revolution $=\frac{20}{4\pi }=\frac{5}{\pi }=1.59$.

Therefore the circular disk completed only one revolution.