Question

A satellite is in a stable circular orbit around the earth. Another satellite is in a stable circular orbit at a greater altitude must have

A. a smaller speed and a shorter period.
B. a smaller speed and a longer period.
C. a greater speed and a shorter period.
D. a greater speed and a longer period.

Answer 1

D. a greater speed and a longer period.

Answer 2

B. a smaller speed and a longer period.


`F_c = m (v^2)/(r) = m (4 \pi^2 r)/(T^2)`


`F_c \propto 1/r`,

`F_c \propto 1/T^2`,

`F_c \propto v^2`.

Therefore, increasing the radius decreases
`F_c`
Deceasing
`F_c` increases the period.
Decreasing
`F_c` decreases the speed.