Answer:
The charges on the spring are 1.23E-5 C and they have the same sign
Explanation:
Given
Coulomb laws states that the force exerted by a charge q on another charge Q at a distance r is given by
F = kqQ/r²
Where k = 8.99 * 10^9 Nm²/C²
r = 0.43 + 0.013
r = 0.443m
The force on the spring is calculated as;.
F = kx where x is the stretch length of the spring and k is the spring constant
The force acting on the spring = 238 * 0.013
F = 3.094N
By comparison;
F = kqQ/r² becomes
3.094 = F = kqQ/r²
kqQ/r² = 3.094 (Considering that a = Q)
kq²/r² = 3.094
8.99 * 10^9 * q²/0.443 = 3.094 -- make q² the subject of formula
q² = 3.094 * 0.443/8.99*10^9
q² = 1.524629588431E−10
q = √1.524629588431E−10
q = 0.000012347589191545C
q = 1.23E-5 C
The charges on the spring are 1.23E-5 C and they have the same sign