Answer:
24 N
Explanation:
Given,
Unstretched length or original length , x1 = 12cm
Stiffness constant, k = 8 N/cm
Load required to take spring to a length , x2 of 15cm
Recall the relation :
F = Ke
Where, e = extension
e = x2 - x1
e = (15 - 12) = 3
F = ke
F = 8 N/cm * 3cm
F = 24 N/cm*cm
F = 24 N
Hence, required load = 24 N