Two charges q1 and q2 are 18cm apart and have an electric force between them of 1micro newton. If the charge on q2 is increased by 9 times and the distance between q1 and q2 changed to 0.621cm, what is the new electric force between them? I've tried doing this question using E=kq/r^2 and F=kq1q2/r^2. I am completely baffled as to how to go about this question! I'm so frustrated please help!