一道大学物理题（由于小弟英语授课）英文题目

一道大学物理题（由于小弟英语授课）英文题目Two small,positively charged spheres have a combined charge of 2.5×10-5C.If each sphere is repelledfrom the other by an electrostatic force of 1N when thespheres are 2 m apart,what is the charge on the spherewith the smaller charge?我感觉应该是一道很简单的物理题首先依题意 q1+q2=2.5X10^-5C 然后由那个库仑定律 F=q1*q2/4πE*r^2=1可以得出一个q1*q2的关系式.但是我怎么算也算不出来.