The moon is about 3,84,000 km from the earth, and its path around the earth is nearly circular. Find the speed at which it orbits earth, assuming that it orbits the earth in 24 hours.

Suppose there existed a planet that went around the sun twice as fast as the earth. What would be its orbital size as compared to that of the earth ?

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 = 6.0Xx10^24 kg , radius = 6400 km.

Both earth andmoon are subject to the gravittional force of the sun. As observed from the sun, the orbit of the moon

A satellite with a 40 cm long copper wire on its bottom is revolving around the earth at 7.8 km per second, such that the wire is perpendicular to the vertical component of earths' magnetic field. Determine the e.m.f. induced across this wire, if the magnitude of the vertical component of magnetic field is 0.2 gauss.

An airforce plane is ascending vertically at the rate of 100 (km)/h . If the radius of the earth is r km, how fast is the area of the earth, visible from the plane, increasing at 3 minutes after it started ascending?Given that the visible area A at height h is given by A=2pir^2h/(r+h)