A planet orbits the sun at a distance of 2.87 x 10^9 km. If the mass of the sun is 1.99 x 10^30 kg, find the orbital period of the planet. Then, calculate the orbital speed of the planet.

Answer 1

R = 2.87 * 10^12 meters
G =6.67*10^-11

G m M = m v^2/R
so
v^2 = G M R
find speed v
then 2 pi R/v = period

Answer 2

I don't understand

Answer 3

Google Newton, universal gravitation F = G m M /R^2
and gravitational force = mass times centripetal acceleration (m v^2/R)

Answer 4

sorry, made algebra error
R = 2.87 * 10^12 meters
G =6.67*10^-11

G m M/R^2 = m v^2/R
so
v^2 = G M / R
find speed v
then 2 pi R/v = period