# Calculating satellites´ period of revolution

## Homework Statement

Earths´ satellite orbits 4200km above Earths surface. Count satellites´ trajectory circle-shaped and calculate satellites´period of revolution.

## The Attempt at a Solution

I added the Earths´ radius to the 4200 km, which represents the orbiting attitude and then my mind crashed...
please some help Related Introductory Physics Homework Help News on Phys.org
LowlyPion
Homework Helper
Welcome to PF.

What is the acceleration of gravity at that height? (Hint: it's not 9.8)

What other acceleration is there from circular motion?

Welcome to PF.

What is the acceleration of gravity at that height? (Hint: it's not 9.8)

What other acceleration is there from circular motion?
Of course the centripetal-acceleration but I thought that I should know the mass of the satellite to calculate the acceleration of gravity...

btw.. thanks for the welcome

LowlyPion
Homework Helper
Of course the centripetal-acceleration but I thought that I should know the mass of the satellite to calculate the acceleration of gravity...

btw.. thanks for the welcome
Since the 2 accelerations will need to offset to stay in orbit, you won't need the mass.

Since the 2 accelerations will need to offset to stay in orbit, you won't need the mass.
yeah, that settles it down, I think I can see the big picture now,
Thank You!