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**1. The problem statement, all variables and given/known data**

a) Common transparent tape becomes charged when pulled from a

dispenser. If one piece is placed above another, the repulsive force can

be great enough to support the top piece’s weight. Assuming equal point

charges (only an approximation), calculate the magnitude of the charge if

electrostatic force is great enough to support the weight of a 10.0 mg

piece of tape held 1.00 cm above another.

**2. Relevant equations**

*F*=

*k |q*1

*q*2| /

*r*

^{2}**3. The attempt at a solution**

I'm getting confused: I know r=1cm and the two pieces of tape have the same charge.

I am certain I need to add the weight in, but how?

I even tried using Newton's Law of gravitation with 10mg being the mass, but that brought no insight.