Inside a uniform spherical shell:

(a) the gravitation field is zero                                    (b) the gravitational potential is zero

(c) the gravitation field is same everywhere            (d) the gravitation potential is same everywhere

(e) all the above

Choose the most appropriate answer from the options given below:

A wire can be broken by a load of 20 kg-wt. The force required to break wire of same material with twice the diameter will be

The radii of circular orbits of two satellites A and B of the earth, are 4R and R, respectively. If speed of satellite A is 2V, then the speed of satellite B will be

At a point away from planet of radius 6400 km, the gravitational potential and field are –6.4 × 10⁷ SI units and 6.4 SI units respectively. Find height of that point above surface of planet.

Mass of moon is $\frac{1}{81}$  times the mass of a planet and radius is $\frac{1}{9}$  times the radius of the planet. The ratio of escape speed from planet to escape speed from moon is ________.

If the gravitational acceleration at the surface of earth is g, then increase in potential energy in lifting an object of mass m from earth surface to a height equal to half of radius of earth from surface will be: