physics highschool level question

Question

If an Alpha particle experience an electric force of 0.31 N at a specific location in space, what electric force would a proton experience at the same location?

Answer 1

The equation which relates electric force and electric field is F_e=q*E. If an alpha-particle (which has charge +2e, where 'e' is the magnitude of the charge of an electron), experiences an electric force F_e, then F_e=2*e*E.

A proton, which has charge +e, at the same location will experience a force F_e^'=e*E. You can see that this is half of the force that the alpha-particle experienced. Therefore, a proton will experience an electric force with magnitude F=0.155 N.