Imagine a new planet having the same density as that of earth but it is 3 times bigger than the earth in size. If the acceleration due to gravity on the surface of earth is g and that on the surface of the new planet is g’ then

A roller coaster is designed such that riders experience "weightlesness" as they go round the top of a hill whose radius of curvature is 20m The speed of the car at the top of the hill is between:

A body weighs 72 N on the surface of the earth. What is the gravitational force on it, at a height equal to half the radius of the earth?

Two spherical bodies of mass M and 5 M and radii R and 2 R released in free space with initial separation between their centres equal to 12 R. If they attract each other due to gravitational force only, then the distance covered by the smaller body before collision is

What will be the formula of the mass in terms of g, Rand G (R=radius of earth)

Two spheres of masses m and M are situated in air and the gravitational force between them is F. The space around the masses is now filled with a liquid of specific gravity 3. The gravitational force will now be

Two astronauts are floating in gravitation free space after having lost contact with their spaceship. The two will

The acceleration due to gravity at a height 1 km above the earth is the same as at a depth d below the surface of earth. Then