Final answer:
The spring constant is found by rearranging Hooke's Law and using the work done by a spring formula. The work to stretch the slingshot 15 cm from equilibrium is calculated using the work calculation for springs once the spring constant is known.
Step-by-step explanation:
The spring constant k is a measure of the stiffness of a spring and it dictates the amount of force required to compress or extend the spring by a certain distance. According to Hooke's Law, F = kx, where F is the force applied, k is the spring constant, and x is the displacement from the equilibrium position.
To calculate the spring constant using the given information, we can rearrange Hooke's Law to solve for k: k = F / x. As per the example provided, if it takes 500 J of work to compress a spring 10 cm (0.1 m), we use energy work done by a spring formula W = 1/2 k x^2, which results in k = 2W / x^2. Thus, k = 2 * 500 J / (0.1 m)^2 = 100000 N/m.
For part b), to calculate the work done to stretch a slingshot 15 cm from equilibrium, we use the same work formula: W = 1/2 k x^2. Once we know the spring constant, we can substitute k and x into this formula to find the work.