Planet A has a mass of 2.25 x 1020 kg, while planet B has a mass of 6.20 x 1018 kg. What is the gravitational attraction
between two planets if the distance between them is 435,500
km? Estimate G as 6.67 x 10-11 N (m/kg) ?

Estimate the kinetic energy of the neptune with respect to the sun as the sum of the terms, that due to its daily rotation about its axis, and that due to its yearly revolution about the sun. [assume the neptune is a uniform sphere with mass = 1.0×1026 kg , radius = 2.5×1010 m , rotation period 16.1 h , orbital period 6.01×104 d and is 4.6×109 km from the sun.]