Answer:
The spring constant of this spring is 200 N/m.
Explanation:
Given:
Original unstretched length of the spring (x₀) = 10 cm =0.10 m [1 cm =0.01 m]
Stretched length of the spring (x₁) = 18 cm = 0.18 cm
Force acting on the spring (F) = 16 N
Spring constant of the spring (k) = ?
First let us find the change in length of the spring or the elongation caused in the spring due to the applied force.
So, Change in length = Final length - Initial length

Now, restoring force acting on the spring is directly related to its elongation or compression as:

Rewriting in terms of 'k', we get:

Now, plug in the given values and solve for 'k'. This gives,

Therefore, the spring constant of this spring is 200 N/m.