Question

A research satellite of mass 200 kg circles the earth in an orbit of average radius $\frac{3R}{2}$ where R is the radius of earth. Assuming the gravitatioaal pull on a mass of 1 kg on the earth's surface to be 10 N, the puII on the sateIlite will be

• A. 880 N
• B. 889 N
• C. 885 N
• D. 892 N

Answer 1

Answer: (B)

889 N

Answer 2

On earth,$mg= 10\, or\, 1 \times g = 10 \Rightarrow g = 10\, ms^{-2}$ Now, \hspace10mm g' = g\frac{R^2}{r^2} = 10 \times \frac{R^2}{(3R/2)^2}=\frac{40}{9} Pull on satellite = m' g' \hspace25mm = 200 \times \frac{40}{9} = 889\, N