Question

Two identical charges, 2 m apart, exert forces of magnitude 4 N on each other. The value of each charge is: 1. 9 × 105 C 2. 4.2 × 10−5 C 3. 3.8 × 105 C 4. 2.1 × 10−5 C 5. 1.8 × 10−9 C

Answer 1

The value of each charge is 4.22 x 10⁻⁵ C

Step-by-step explanation:

Given;

distance between the two identical charges, d = 2 m

the force of repulsion between these two charges, F = 4N

Apply Coulomb's law;

`F = (kq_1q_2)/(r^2) \\\\but \ q_1 =q_2,then \ let \ q_1 =q_2 = q\\\\F = (kq^2)/(r^2)\\\\q^2 = (Fr^2)/(k)\\\\q^2 = (4*2^2)/(9*10^9) \\\\q ^2 = 1.7778*10^(-9)\\\\q = \sqrt{1.7778*10^(-9)}\\\\q =4.22 *10^(-5) C\\\\q= q_1=q_2= 4.22 *10^(-5) C`

Therefore, the value of each charge is 4.22 x 10⁻⁵ C