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Hi. So my friend had a physics question:
A satellite of 1000 kg in orbit around earth is at 5.6E6 meters in altitude and 7100 m/s at perigee (so Rp=11971000 and Vp=7100). His task was to use conservation of energy and conservation of angular momentum to find radial distance and velocity at apogee. Solving
mRpVp=mRaVa
and
.5*m*vp^2 - GMm/rp = .5*m*va^2 - GMm/ra
I got velocity at apogee to be 2300 m/s. But simulating this problem in orbiter, it says velocity should be 1361. I'm wondering where I went wrong. Because 2300 m/s and the corresponding radius (which can easily be calculated from va=2300 m/s) satisfies both of the above equations, while orbiter's value of 1361 does not. Thanks for any help.
A satellite of 1000 kg in orbit around earth is at 5.6E6 meters in altitude and 7100 m/s at perigee (so Rp=11971000 and Vp=7100). His task was to use conservation of energy and conservation of angular momentum to find radial distance and velocity at apogee. Solving
mRpVp=mRaVa
and
.5*m*vp^2 - GMm/rp = .5*m*va^2 - GMm/ra
I got velocity at apogee to be 2300 m/s. But simulating this problem in orbiter, it says velocity should be 1361. I'm wondering where I went wrong. Because 2300 m/s and the corresponding radius (which can easily be calculated from va=2300 m/s) satisfies both of the above equations, while orbiter's value of 1361 does not. Thanks for any help.
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