Turn on thread page Beta
 You are Here: Home >< Physics

# Circular Motion watch

1. I have a quick question, and it might seem silly, in that it will probably seem obvious as soon as I hear the answer, but I'm tired and stuck and I just want to finish my homework.
The question is as follows:

A satellite orbits the Earth once every 97 minutes.

a) Calculate the angular velocity.
I've worked this out to be 1.08x10^-3. (I know it should be to 2s.f.)

b) Calculate the radius of the orbit.
This is where I get stuck. I have all of the equations in front of me, but I can't figure out how to combine them to have r in the equation without having to know the linear velocity.

I know that v=(2pi r)/T and v=wr, but when I try to equate them the r just cancels out, and I basically just don't know. It seems like I have to know v to know r, but I also have to know r to know v.

Any kind of hint is appreciated. Thanks in advance!
2. Just trying to bump this up in latest discussions because I really need to know.
3. I'd try assuming the centripetal acceleration equalled g and using
a=ω2 r
4. (Original post by Joinedup)
I'd try assuming the centripetal acceleration equalled g and using
a=ω2 r
I ended up figuring out, but thank you

Reply
Submit reply
Turn on thread page Beta

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: June 26, 2016
Today on TSR

### Edexcel GCSE Maths Unofficial Markscheme

Find out how you've done here

### AQA Maths Paper 1 exam discussion

Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.