# What is the force, in terms of Coulomb's constant, between two electrical charges of -45 C and 25 C that are 15 m  apart?

May 6, 2016

$F = - 4.5 \cdot {10}^{10} N$

#### Explanation:

$\text{Force between two electric charges is given as:}$
$F = k \cdot \frac{{q}_{1} \cdot {q}_{2}}{r} ^ 2$

$\text{where " k=9*10^9" "q_1=-45C" "q_2=25C" } r = 15 m$

$F = 9 \cdot {10}^{9} \cdot \frac{\left(- 45\right) \cdot 25}{15} ^ 2$

$F = - 9 \cdot {10}^{8} \cdot \frac{45 \cdot \cancel{25}}{\cancel{225}}$

$F = - \cancel{9} {10}^{9} \cdot \frac{45}{\cancel{9}}$

$F = - 45 \cdot {10}^{9}$

$F = - 4.5 \cdot {10}^{10} N$