Answer: 16N
Explanation:
According to Coulomb's law, the force existing between two charges is directly proportional to the product of their charges and inversely proportional to the distance between the charges. Mathematically,
F = kq1q2/r²
Where F is the force between them
q1 and q2 are the charges
r is the distance between them.
If the force between them is 10N, the formula becomes;
10 = kq1q2/r²... (1)
If the distance between them is now halved, the force will become
F = kq1q2/(r/2)²
F = kq1q2/(r²/4)
F = 4kq1q2/r² ... (2)
Dividing equation 1 by 2 we have;
4/F = (kq1q2/r²)÷ (4kq1q2/r²)
4/F = kq1q2/r²×r²/4k1q1q2
4/F = 1/4
Cross multiplying we have;
F = 4×4
F = 16N
Therefore the new force between the charges is 16N
