Final answer:
To find the spring constant k of the spring, we can use Hooke's Law, which states that the force exerted by a spring is proportional to the displacement from its equilibrium position. We can calculate the force needed to stop the subway train using the equation F = ma. Then, we can calculate the spring constant k using Hooke's Law.
Step-by-step explanation:
To find the spring constant k of the spring, we can use Hooke's Law, which states that the force exerted by a spring is proportional to the displacement from its equilibrium position.
- First, let's calculate the force needed to stop the subway train using the equation F = ma, where F is force, m is mass, and a is acceleration.
- Next, we can calculate the spring constant k using Hooke's Law, which states that F = -kx, where F is force, k is the spring constant, and x is the displacement from the equilibrium position.
Using the calculations, the spring constant k of the spring is 1.56 × 10^6 N/m (option d).