A research satellite of mass 200 kg circl

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A research satellite of mass $200 \,kg$ circles the earth in an orbit of average radius $3\,R/2$ where $ R$ is the radius of the earth. Assuming the gravitational pull on a mass of $1 \,kg$ on the earth’s surface to be $10 \,N$, the pull on the satellite will be ........ $N$. 

A

$889$

B

$880$

C

$890$

D

$892$

A research satellite of mass $200 \,kg$ circles the earth in an orbit of average radius $3\,R/2$ where $ R$ is the radius of the earth. Assuming the gravitational pull on a mass of $1 \,kg$ on the earth’s surface to be $10 \,N$, the pull on the satellite will be ........ $N$. 

$g' = g\,{\left( {\frac{R}{{R + h}}} \right)^2} = g\,{\left( {\frac{R}{{3R/2}}} \right)^2} = \frac{4}{9}g$  

$W' = \frac{4}{9} \times mg = \frac{{4 \times 200 \times 9.8}}{9} = 889\;N$