orbit question (1 Viewer)

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my teacher will rip my head off for saying centripal force...hmm...another force....orbital decay?? how the satellite gradually spirals down towards the earth because of the contact between atmosphere drag and the satellite??

 

[Lazarus]

Originally posted by ...
hmm...another force....orbital decay?? how the satellite gradually spirals down towards the earth because of the contact between atmosphere drag and the satellite??

Mmm... friction (i.e. atmospheric drag) is certainly a force. I think it only really applies to LEOs though... can be avoided if the satellite is orbiting further out. Probably still worth mentioning.

 

[Ragerunner]

but that won't answer the question ?

atmospheric drag isn't what maintains a space station in orbit. that is what brings it down

 

[Lazarus]

Originally posted by Ragerunner
atmospheric drag isn't what maintains a space station in orbit. that is what brings it down

Yes, it causes the satellite's orbit to decay - and so obviously, something else (e.g. greater velocity or greater orbital radius) must compensate in order to maintain the orbit...

 

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k, so we need to know WHY the satellite is orbiting in its orbit...

the reason i can think of is that the satellite was launched at an correct velocity(orbital velocity) and therefore, it will orbit...if u dun understand me, u can think of it as Newton's idea where u shoot a cannon off a mountain, if the cannon is fast enough, the thing will orbit the earth and never come down...

the force(not in the original q's) acting between the satellite and earth can only be gravity, centripal force is is gravity.(think of it as holding a string and swing a weight attached to the end of it, centripal force on the weight is the string and in this case, its gravity, just cos its invisible, it still exist). There should only be one force acting on the satellite and thats gravity...if this isn't the case, the orbital velocity formula will be wrong