A moon of mass 4.00 1015 kg is in a circular orbit of radius ...

[maychende]

A moon of mass 4.00  1015 kg is in a circular orbit of radius 1.00  105 km about a planet of mass 6.00  1020 kg. Determine the potential energy of the system.
 
  A)
 
  1.60  1010 J
  B)
 
  2.40  1031 J
  C)
 
  -1.60  1010 J
  D)
 
  -6.67  105 J
  E)
 
  -1.60  1018 J

Question 2

A charge Q is uniformly distributed throughout a nonconducting sphere of radius R.
 
  (a) What is the magnitude of the electric field at a distance R/2 from the center of the sphere? (b) What is the magnitude of the electric field at a distance 2R from the center of the sphere?

[pami445]

Answer to Question 1

E

Answer to Question 2

(a) Q/8 OR2
(b) Q/16 OR2

[maychende]

Gracias!

[matt95]

Thanks for the timely response, appreciate it