The star's mass is 1.6×1030 kg, and the planet orbits at 1.02×1011 m from the star.

Question

What is the planet's orbital velocity, in km/s?  

 

 

Answer 1

Mass of the planet M =1.6 × 10³⁰   kg

Universal gravitational constant, G = 6.673× 10^-11  m³ kg^-1 s^-2

Radius of the planet, r =1.02× 10¹¹ m

Calculate the  orbital velocityof the planet by using the following formula:

v = √(G M/r)

 

v =√((6.673× 10^-11) (1.6 × 10³⁰)/(1.02× 10¹¹))

  = 32353.44 m/s

   = 32.35 km/s

 

Therefore, the orbital velocityof the planet is 32.35 km/s