MediumPhysicsHigh School (11–12)Mechanics › GravitationNumerical

A polar satellite orbits 800 km above the Earth.

Try it on paper first. A hint, the key idea and the worked solution are here when you need them.

A polar satellite orbits $800\ \text{km}$ above the Earth. Find its period, the number of orbits it makes in a day, and how far west along the equator its track moves from one orbit to the next. ( $GM = 4.01 \times 10^{14}\ \text{m}^3/\text{s}^2$ , $R = 6400\ \text{km}$ ; the Earth turns once in $86\,164\ \text{s}$ .)

Need a reminder? The key ideaShow

In a circular orbit of radius $r$ : $v = \sqrt{\dfrac{GM}{r}}$ , $T = 2\pi\sqrt{\dfrac{r^3}{GM}}$ , independent of the satellite's mass. Its energies: $K = \dfrac{GMm}{2r}$ , $U = -2K$ , $E = -K$ .

The worked solution

Have you tried it?

Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.

← All Problems

← A satellite goes round the Earth once every 8 hours.A 62 kg student stands on a scale in a lift. →

More onMechanics › Gravitation

Discussion (0)

Loading…