Overview

When a soap bubble is illuminated by source of white light, it appears coloured. This is due to

If the earth suddenly stop rotating, the value of ‘g’ at the equator would

Energy required to shift a body of mass m from an orbit of radius 2R to 3R is (mass of planet is M)

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

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 $\frac{1}{81}$ <!-- [if gte mso 9]><xml> </xml><![endif]--> times the mass of a planet and radius is $\frac{1}{9}$ <!-- [if gte mso 9]><xml> </xml><![endif]--> 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:

Gravitational force between two point masses is found to be F when both are in vacuum. If both the masses are immersed in water, new gravitational force will be: