Final answer:
The potential energy stored in a spring with a constant of 120 N/m stretched 0.2 m is 2.4 J, calculated using the formula PE = (1/2)kx^2.
Step-by-step explanation:
The question involves calculating the potential energy stored in a spring with a known spring constant as it is stretched. According to Hooke's law, the potential energy (PE) stored in a spring stretched or compressed by a distance x from its equilibrium position is given by the equation PE = (1/2)kx2, where k is the spring constant and x is the displacement.
In this case, the spring constant k is given as 120 N/m, and the displacement x is 0.2 m. Plugging these values into the formula:
PE = (1/2)(120 N/m)(0.2 m)2 = (1/2)(120)(0.04) = 2.4 J.
Therefore, the amount of potential energy stored in the spring is 2.4 J when it is stretched 0.2 m.