MYTUTOR SUBJECT ANSWERS

339 views

What speed do satellites orbit at?

The key point to recognise here is that an object undergoing a circular orbit around the Earth is undergoing circular motion. Circular motion is caused by a centripetal force (acting towards the centre of the circle), described by:

F= msatellitev2/r   (eq 1)

In the case of an orbit, the force acting towards the centre is due to the gravity of the Earth, which is described by Newton's law of universal gravitation:

F= GmEarthmSatellite/r2  (eq 2)

We can now equate these two expressions:

Fc = Fg => msatellitev2/r = GmEarthmSatellite/r2  (eq 3)

Now me can rearrange to make v the subject of the equation:

v = sqrt(GmEarth/r)   (eq 4)

This is the speed of a satellite in a circular orbit around the Earth. Note that v is proportional to 1/sqrt(r) and that the mass of the satellite has cancelled out.

Ryan M. Mentoring Physics tutor, GCSE Maths tutor, GCSE Science tutor...

1 year ago

Answered by Ryan, an A Level Physics tutor with MyTutor

Still stuck? Get one-to-one help from a personally interviewed subject specialist

50 SUBJECT SPECIALISTS

£20 /hr

William D.

Degree: Mechanical Engineering (Masters) - Leeds University

Subjects offered: Physics, Maths+ 2 more

Physics
Maths
Italian
Chemistry

“I am a British student currently in the first year of a masters degree in Mechanical Engineering at the University of Leeds. Having previously lived in Spain and Italy, I am fluent in both languages and have excellent communications s...”

MyTutor guarantee

£20 /hr

Oscar Z.

Degree: General Engineering (Bachelors) - Durham University

Subjects offered: Physics, Maths+ 1 more

Physics
Maths
Further Mathematics

“I am a second year General Engineering student at Durham University. I have a passion for science and technology and often find delight in finding out how things work. Richard Feynman (Nobel Laureate) puts it better! https://www.youtu...”

£20 /hr

Riccardo P.

Degree: Physics (Bachelors) - Imperial College London University

Subjects offered: Physics, Maths+ 1 more

Physics
Maths
Italian

“Hi, I'm Riccardo, a physics fresher at London's Imperial College from Milan. As you can imagine I really like physics and maths, but that doesn't mean I'll spend all my time studying! I'm an active guy who loves sports (boxing, diving ...”

MyTutor guarantee

About the author

Ryan M.

Currently unavailable: for new students

Degree: PhD in Astronomy (Doctorate) - Cambridge University

Subjects offered: Physics, Science+ 2 more

Physics
Science
Maths
Further Mathematics

“About Me:I'm a recent Physics graduate of Oxford University (1st Class Honours), currently working on a PhD in Astronomy at Cambridge University. My Astrophysics research is focused on characterising the atmospheres of planets orbit...”

You may also like...

Posts by Ryan

What speed do satellites orbit at?

Where does the quadratic equation come from?

Why is Pluto not a planet any more?

Other A Level Physics questions

What is the difference between accuracy and precision?

What is meant by the binding energy of a nucleus?

Explain Rutherford's atomic model experiment

Explain what simple harmonic motion means?

View A Level Physics tutors

Cookies:

We use cookies to improve our service. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok