A rocket is fired from the earth towards the sun. At what distance form the earth's centre is the gravitational force on the rocket zero? Mass of the sun `= 2 xx 10^20` kg and mass of earth `= 6 xx 10^24` kg and orbital radius `1.5 xx 10^-8` km.

What is the magnitude of the gravitational force between the earth and a 1 kg object on its surface? (Mass of the earth is 6 x 10^24 kg and radius of the earth 6.4 x 10^6 m.)

Calculate the force of gravitation between the earth and the Sun, given that the mass of the earth = 6 xx 10^24 kg and mass of the Sun = 2 xx 10^30kg . The average distance between the two is 1.5 xx 10^11 m .

A satellite orbits the earth at a height of 400 km above the surface. How much energy must be expended to rocket the satellite out of the earth’s gravitational influence? Mass of the satellite = 200 kg, mass of the earth = 6.0 xx10^24 kg, radius of the earth = 6.4 xx10^6 m, G = 6.67 x 10^-11 N m^2 kg ^-2 .

A planet's year is 11 times the earth's year. Calculate the distance of this planet from the sun if the distance of the earth is 1.50xx10^8 km from the sun.

A saturn year is 29.3 times the earth year. How far is the saturn from the sun if the earth's 1.5 xx 10^8 km away from the sun.

As you have learnt in the text, a geostationary satellite orbits the earth at a height of nearly 36,000 km from the surface of the earth. What is the potential due to earth’s gravity at the site of this satellite? (Take the potential energy at infinity to be zero). Mass of the earth = 6.0 xx 10^24 kg, radius = 6400 km

A spaceship is stationed on Wlars. How much energy must be expended on the spaceship to launch it out of the solar system? Mass of the space ship = 1000 kg, mass of the Sun = 2 xx 10^30 kg, mass of mars = 6.4 xx-10^23 kg, radius of mars = 3395 km, radius of the orbit of mars = 2.28 x 10^8 kg, G= 6.67 xx 10^-11 m^2kg-^2 .

An artifucial satellite is orbiting around the earth with a speed of 4kms_-1 at a distance of 10^4 km from the earth. Calculate the centripetal acceleration.

Gravitational force on the surface of the moon is only 1/6 as strong as gravitational force on the earth. What is the weight in newtons of a 10 kg object on the moon and on the earth?