Calculating satellites´ period of revolution

AI Thread Summary
To calculate the period of revolution for a satellite orbiting 4200 km above Earth's surface, the Earth's radius must be added to the altitude. The acceleration of gravity at that height differs from the standard 9.8 m/s², and centripetal acceleration must also be considered. Importantly, the mass of the satellite is not needed for this calculation, as the gravitational and centripetal accelerations will balance each other. Understanding these concepts clarifies the overall approach to solving the problem. This foundational knowledge is essential for accurately determining the satellite's orbital period.
JukuJohannes
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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 helpo:)
 
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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?
 
LowlyPion said:
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
 
JukuJohannes said:
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.
 
LowlyPion said:
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!
 

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