Question

2. The Moon orbits the Earth in a nearly circular orbit at a distance of about240,000 miles.b. If the Moon takes approximately 27.3 days for one round trip, whatis its average velocity in km/hr?

Answer 1

For this case we know that the Moon orbits the Earth in a circular orbit at a distance of about 240000 miles, we also know that for one complete trip it takes about 27.3 days and we want to estimate the average velocity in km/hr

The first step here is convert the miles into km and the days into hours and we got this:

`r=240000mi\cdot(1.609Km)/(1mi)=386160Km`
`27.3\text{days}\cdot(24hr)/(1day)=655.2hr`

After this we know that the total circumference of a circle is given by:

`S=2\pi r`

And from here is possible to find the distance covered in one orbit:

`S=2\pi(386160Km)=2426314.838Km`

And then we can use the definition of velocity given by:

So for this case we can conclude that the average velocity for the Moon is given by 3703.167 Km/hr