# Two balloons with an identical charge are at a distance of 12 cm. If the force of repulsion is 5.48 mN what is the charge on them.

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The force of repulsion between two bodies with a charge C1 and C2 and which are at a distance d from each other is given by `F = (k*C1*C2)/d^2` where k `~~` 8.987*10^9 `(N*m^2)/C^2`

The two balloons have an identical charge on them and are at a distance 12 cm from each other. Let the charge on them be C. Substituting these values in the equation gives:

`5.48*10^-3 = (8.987*10^9*C^2)/0.12^2`

=> `C^2 = (5.48*10^-3*0.12^2)/(8.987*10^9)`

=> C = 9.037*10^-8 C

**The magnitude of the charge on each of the balloons is 9.037*10^-8 C**