Question

A body covers a semicircle of radius 7cm in 5s .find its linear speed

Answer 1

Ok so we are given the radius of 7cm and time of 5 seconds.

From the data we got we can calculate speed, frequency, perimeter and area of the semicircle.

Let's start with perimeter.

We know that perimeter of circle is
`2\pi r` so the perimeter of semicircle is
`(2\pi r)/(2)` or simply
`\pi r`

So the perimeter is equal to:

`\pi r=\pi\cdot7\approx\boxed{22cm}`

So this is the length of a curve or let's say the distance.

Now let's look at the linear speed
`s=(d)/(t)` where d is distance and t time.

We know the distance and we know the time.

So let's calculate it.

`s=(d)/(t)=(22)/(5)=\boxed{4.4(cm)/(s)}`

Hope this helps.

r3t40