With what velocity should a particle be projected so that its height becomes equal to radius of earth?
If the sum of the areas of two circles with radii R1 and R2 is equal to the area of a circle of radius R, then
The masses and radii of the earth and moon are M1,R1 and M2,R2 respectively. Their centres are distance d apart. The minimum velocity with which a particle of mass m should be projected from a point midway between their centres so that it escapes to infinity is