Two particles of equal mass go around a circle of radius R under the action of their mutual gravitational attraction. Find the speed of each particle.

Options

A. `1/(2R)sqrt(1/(Gm))`
B. `sqrt("Gm"/"2R")`
C. `1/2sqrt("Gm"/R)`
D. `sqrt((4Gm)/R)`

Answer

C

Explanation

Centripetal force provided by the gravitational force of attraction between two particles i.e.

`(mv^2)/R=(G.mxxm)/((2R)^2)`
`therefore V=1/2sqrt((Gm)/R)`