How much fuel is required?

1. Draw the initial and final orbits. Draw the orbit that the GPS module has to follow if it is to leave the low orbit tangentially and reach the high orbit tangentially.
2. Write down the expressions for the angular momentum of the module.
   1. immediately after the energy boost
   2. as it reaches the high orbit
3. How is the velocity immediately after the energy boost related to the velocity of the module as it reaches the higher orbit?
4. How is the kinetic energy of the module as it reaches the higher orbit related to the kinetic energy of the module immediately after the boost and to the work that needs to be done against the gravity pull?
5. Calculate the kinetic energy that the module needs immediately after the boost if it is to complete the transfer as indicated.
6. Subtract the kinetic energy before the boost from the kinetic energy after the boost.

   If you need more extensive hints, step through the Hint Movie