Question

A satellite circles planet Roton every 3.6 hours in an orbit having a radius of 1.8 x 10^6 m. What is the mass of this planet?

Answer 1

Given,

radius of orbit (r) = 1.8 x 10⁶ m

time period(T) = 3.6 h = 3.6 x 60 x60 s = 12960 s  

The angular speed of the satellite( )

Speed of satellite,

  

The speed of satellite is given by,

  

Where, G = 6.67 x 10-11 m3 kg-1 s-2 is universal gravitational constant

M is mass of planet

r = 1.8 x 10⁶ is radius of satellite's orbit

Putting all values in the above equation, we get

or,   

or,

or,

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