two particles of equal masses move in a circle of radius r under the action of their mutual gravitational
uttraction. Find the speed of each particle if its mass is m.

Explanation

The particles will always remain diametrically opposite so that the force on each particle will be directed
blong the radius. Considering the circulation of one particle, we have .
`("MV"^(2))/(r)=("Gmm")/((2r)^(2)),`i.e., `V= sqrt("Gm"/(4r))`