Question

The separation between the two charged objects is 20 cm and the charge on each object is
13 uC. Calculate the magnitude of the repulsive force between the two charged objects?​

Answer 1

Given :

Two charges of 13 μC are placed at a distance of 20 cm away from each other.

To Find :

Magnitude of the repulsive force between both objects.

Solution :

• The magnitude of electrostatic force between two point charges is directly proportional to the product of charges and inversely proportional to the square of the distance between them. This is known as Coulomb's law also known as inverse square law.

Mathematically,

$\large{\dag}\:\underline{\boxed{\bf{\orange{F=k\:\dfrac{q_1\times q_2}{r^2}}}}}$

• k = 9 × 10⁹ N m² / C²
• q₁ = q₂ = 13 × $\sf{10^{-6}}$
• r = 0.2 m

By substituting the values;

$\sf:\implies\:F=k\:\dfrac{q_1\times q_2}{r^2}$

$\sf:\implies\:F=(9\times10^9)\dfrac{(13\times 10^{-6})^2}{(0.2)^2}$

$\sf:\implies\:F=\dfrac{1521\times10^{-3}}{0.04}$

$:\implies\:\underline{\boxed{\bf{\gray{F=38.02\:N}}}}$