An unstrained horizontal spring has a length of 0.34 m and a spring constant of 180 N/m. Two small charged objects are attached to this spring, one at each end. The charges on the objects have equal magnitudes. Because of these charges, the spring stretches by 0.024 m relative to its unstrained length. Determine (a) the possible algebraic signs and (b) the magnitude of the charges. g

a

            ,

OR

              ,    

b

and

Explanation:

Generally the force exerted on the string is mathematically represented as

substituting values 180 N/m for k and 0.024 m for e

This force can also equivalent to the electrostatic force between the charges i.e

substituting for k and ( 0.34 + 0.024 = 0.364 m) for r we have

Given the spring was stretched it means that the force between the charges is a repulsive for which tell us that both charge are of the same sign thus the possible  algebraic signs  of the charges are

            ,

OR

,