1) Consider a heavenly body which has a mass twice that of the Earth and radius thrice that of the Earth. What will be the weight of the book on this heavenly body , if its weight on Earth is 900 N ?

2) Why gravitational force is usually unnoticeable ?

3) Prove that acceleartion due to gravity is independent of mass of the body.

4) How can the average density of the Earth can be determined ?

5) Buoyancy depends on which factors ?

For earth,

Mass of earth = M

Radius of earth = R

Mass of the body = m

Weight on earth is, W_{e} = GMm/R^{2} = 900 N

For the heavenly body,

Mass = 2M

Radius = 3R

So, weight is, W_{p} = G(2M)(m)/(3R)^{2}

=> W_{p} = (2/9)(GMm/R^{2})

=> W_{p} = (2/9)(900)

=> W_{p} = 200 N

This is the weight of the object on the heavenly body.

For help with more answers you may post them individually.

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