Question

How fast is a point on the equator moving as the Earth rotates on its axis? Assume that theEarth has a diameter of 7920 miles and answer in miles per hour.

Answer 1

The distance traveled is the circumference of the equator, and the time taken to travel that distance is 24 hours

Speed at the Equator The earth rotates about its axis once every 24hrs

and the radius of the earth is diameter/ 2

`\begin{gathered} \text{radius = diameter/2} \\ r=(d)/(2)=(7920)/(2)=3960\text{miles} \end{gathered}`

linear speed of a point on the equator is measured in miles per hour

`v=(d)/(t)=(2\pi r)/(t)`
`\begin{gathered} V=(2r\pi)/(t) \\ \text{where } \\ 2r=\text{diameter} \\ \pi=3.14 \\ v=(7920(3.14))/(24)=(24868.8)/(24)=1036.2\text{miles per hour} \end{gathered}`

Therefore the speed of the equator moving as the earth rotates = 1036.2 miles per hour