Law of universal gravitation and satellites (1 Viewer)

[velox]

Describe how the use of this law (law of universal gravitiation) allows calculation of the motion of satellites?

Is it just showing the centripetal force required for the satellite to maintain so that it stays in orbit? So then we can calculate the speed required at a certain distance?

 

[velox]

anyone?
fkntenchars

 

[Xayma]

Yes. A manipulation of the gravitational force and the centripetal motion required to keep them in orbit, since these are equal a velocity can be calculated for a specific altitude.

 

[velox]

cool thanks, but how would you know the centripetal force/gravitational force required?

 

[shannonm]

Fgrav = GMm/r^2
let it equal ma(centrip) which = m.r.(omega)^2
r^3 = GM/(omega)^2 = GMT^2/2^2.pi^2

r = cubed root(GMT^2/2^2pi^2)
height = radius - rad earth
v = 2.pi.r/T

 

[zenger69]

cool thanks, but how would you know the centripetal force/gravitational force required?

Centripetal force = gravitational force for a sattelite orbiting the earth.

So just use the equation Gm1m2/r^2 , find the altitude and mass and then work it out.

Thats the force needed to keep in motion.

 

[velox]

oh damn, i should have known that. thanks