# Homework Help: Shuttle, cable and satellite

1. Jan 25, 2010

### Masafi

A satellite was connected to the shuttle by a long, conducting cable, the satellite being in the higher orbit. As the shuttle orbited through the Earth’s magnetic field, an e.m.f. was induced in the conducting cable.

The shuttle, cable and satellite were all moving through the ionosphere, which contains many charmed particles. The charged particles were able to complete a circuit, allowing a current to flow through the cable. One result of this current was that the orbit height of the shuttle, cable and satellite gradually became less.

Explain
(a) the origin of the induced e.m.f.,
(b) the reduction in the orbit height due to the flow of current

a) The origin of the induced e.m.f:
As conductor cuts field lines
Electrons experience force along wire
move to one end --> e.m.f.

(b) Reduction in orbit height due to flow of current:
Current + field --> force OR Fleming L H rule
Lenz’s law:
Force opposes motion
Orbiting craft lose energy/speed

I dont understand the last 2 points of (a) and all of (b)