$Assertion$ : A balloon filled with hydrogen will fall with acceleration $\frac{g}{6}$ of the moon

$Reason$ : Moon has no atmosphere.

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 …….. $N$. 

If the earth rotates faster than its present speed, the weight of an object will

Obtain an expression for the variation in effective gravitational acceleration $g'$ with latitude due to earth’s rotation.

The diameters of two planets are in ratio $4:1$ . Their mean densities have ratio $1:2$ . The ratio of gravitational acceleration on the surface of planets will be