A homogeneous spherical heavenly body has a uniform and very narrow frictionless duct along its diameter. Let mass of the body be `M` and diameter be `D`. A point mass `m` moves smoothly inside the duct. Force exerted on this mass when it is at a distance `s` from the centre of the body is (numerically)

A tunnel is dug along a diameter of the earth. Find the force on a particle of mass m placed in the tunnel at a distance x from the centre.

A body of mass m is moved from the centre of the earth to a infinite distance from its centre. The value of g will

Suppose a holes is drilled completed through the earth along a dimeter. Mass and radius of Earth are M and R . What is the force acting on a body of mass m at a distance r from the centre of Earth?

(a) A tunnel is dug along a diameter of the earth. Find the force on the a particle of mass m placed in the tunnel at a distance x from the centre. (b) A tunnel is dug along a chord of the earth at a perpendicular distance R//2 from the earth's centre. the wall of the tunnel may be assumed to be frictionless. Find the force exerted by the wall on a particle of mass m when it is at a distance x from the centre of the tunnel.

Suppose a verticle tunnel is dug along the diametal of earth , which is assumed to be a sphere of unifrom mass density rho . If a body of mass m is throws in this tunal, its acceleration at a distance y from the centre is given by

Energy required in moving a body of mass m from a distance 2R to 3R from centre of earth of mass M is

A body of mass 3 kg at rest is acted upon by a force and the body moves through a distance 20 m in 5 s. Force on the body is

A solid sphere of mass M and radius R has a spherical cavity of radius R/2 such that the centre of cavity is at a distance R/2 from the centre of the sphere. A point mass m is placed inside the cavity at a distanace R/4 from the centre of sphere. The gravitational force on mass m is