what is the ratio of electrostatic force to gravitational force between two protons separated at same deitance?[mass of proton=1.67*10^-27kg and e= 1.6*10^-19 c].

Gravitational force between two objects is given by F=G(m1)(m2)/(r^2). G is the universal gravitational constant with the value of 6.67*10^-11. m is the rest mass of a proton, at 1.67*10^-27 kg.

Electrostatic force between two charges is given by F=(q1)(q2)/(4πεο r^2). εο is the permittivity of free space with the value of 8.85*10^-12. q is the charge of a proton, a 1.60*10^-19 C.

Assuming their distance is constant, the ratio of gravitational to electrostatic force is basically G(m1)(m2) : (q1)(q2)/(4πεο).

Plugging in the numbers, you'll find that the electrostatic force is 1.236*10^36 times stronger than the gravitational force. This should come as no surprise however as gravitational force is considered the weakest of the four fundamental forces in our universe.