Earth can be thought of as a sphere of radius 6400 km.Any object (or a person) is pewrforming circular motion around the axis of the earth due to the earth rotation (period 1 day). What is acceleration of object on the surface of the earth (at equator) towards its centre? What is it at latitude `theta`? How does these acceleration compare with `g = 9.8 m//s^(2)`?

Earth also moves in circular orbit around the sun once every year with an orbital radius of 1.5xx10^(11)m . What is the accerelation of the earth ( or any object on the surface of the earth) towards the centre of the sun? How does this acceleration compare with g = 9.8 m//s^(2) ?

An object of mass m is raised from the surface of the earth to a heigt equal to the radius of the earth , that is, taken from a distance R to 2R from the centre of the earth. What is the gain in its potential energy?

A satellite is launched into a circular orbit 1600 km above the surface of the earth. Find the period of revolution, the radius of the earth R = 6400 km and the acceleration due to gravity is 9.8 m//sec^2 .

The acceleration due to gravity on the surface of moon is 1.7 m s^-2 . What isthe time period of a simple pendulum on the surface of moon if itstime period on the surface of earth is 3.5 s? (gon the surface of earth is 9.8 m s6-2 )

A solenoid 60 cm long and of radius 4.0 cm has 3 layers of windings of 300 turns each. A 2.0 cm long wire of mass 2.5 g lies inside the solenoid (near its centre) normal to its axis, both the wire and the axis of the solenoid are in the horizontal plane. The wire is connected through two leads parallel to the axis of the solenoid to an external battery which supplies a current of 6.0 A in the wire. What value of current (with appropriate sense of circulation) in the windings of the solenoid can support the weight of the wire? g = 9.8 m s^-2 .