Question

A +5.0 µC charge is placed at the origin and a -3.9 µC charge is placed at x = 25 cm. At what coordinates can a third charge be placed so that it experiences no net force?
E1=k•q1/(x+ Δx)² (to the right)
E2= k•q2/(Δx)² (to the left)
E1= E2
k•q1/(x+ Δx)² = k•q2/(Δx)²
q1•(Δx)² = q2• (x+ Δx)²= q2• (x²+ 2•x•Δx + Δx²)
5• Δx²=3.9(0.0625+0.5 Δx + Δx²)
1.1 Δx² -1.95• Δx -0.24375 =0
Δx = {1.95±√(1.95²+4•1.1•0.24375)}/2.2=
=(1.95±2.21)/2.2= 1.89 m and -0.12m (extraneous root)
Δx =1.89 m

Related Questions

A 6 µC charge is placed at the origin and a second charge is placed on the x-axis at x = 0.34 m. I... Consider a charge of +2.0 C placed at the origin of an X-Y co-ordinate system and a charge of -4.0... Charge A, +1 μC, is positioned at the origin of a coordinate system as shown below. Charge B, −1 μC,... A +33.0 nC charge is placed at the origin of an xy-coordinate system, and a −25.0 nC charge is place...