What is the force between two balloons with a negative charge of 1.6 X 10^-10 C if the balloons are 5.0 cm apart?

Correct  Fc = 9.22 10⁻¹⁷ N

Explanation:

The formula for calculating the Coulomb force between two charged objects, in this case balloons is:

Fc = k · q₁ · q₂ / r² Coulomb force

where it was given:

k = 9 · 10⁹ N m²/C² dielectric constant,

q₁ = q₂ = q =  - 1.6 · 10⁻¹⁰ C

r = 5 cm = 5 · 10⁻² m   distance between charges

Since the given charges are both negative there is a repulsive force between them.

Fc = k · q² / r² = 9· 10⁹ ·  (1.6 · 10⁻¹⁰)² / (5 · 10⁻²)²

Fc = 9· 10⁹ ·  2.56 · 10⁻²⁰ / 25 · 10⁻⁴ = 0.922 10⁻¹⁶ = 9.22 10⁻¹⁷ N

Fc = 9.22 10⁻¹⁷ N

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