Chapter 12, Problem 45SGR

To determine

To find: Period of the function.

Answer to Problem 45SGR

Period of the function $=15$ seconds

Explanation of Solution

Given information:

Diameter of wheel $=d=18$ inches

Wheel completes $4$ revolutions in $1$ minute.

Given

Wheel completes $4$ revolutions in $1$ minute.

It means

  $4$ revolutions $\to 1$ minute

Dividing with $4$ on both sides

We get

  $\Rightarrow$ $\frac{4}{4}$ revolutions $\to \frac{1}{4}$ minute

  $\Rightarrow$ $1$ revolution $\to \frac{1}{4}$ minute

We know

  $1$ minute $=60$ seconds

Using that

We get

  $\Rightarrow$ $1$ revolution $\to \frac{1}{4}\times 60$ seconds

  $\Rightarrow$ $1$ revolution $\to 15$ seconds

Time taken to make one revolution is $15$ seconds.

So,

Period of the function $=15$ seconds