a force of 8 pounds required to pull a spring 1 / 2 feet
beyond the normal length. Determine the spring constant and the amount of work that
required to pull the spring before?

Question

a force of 8 pounds required to pull a spring 1 / 2 feet
      beyond the normal length. Determine the spring constant and the amount of work that
      required to pull the spring before?

anonymous · Answer

By using Hooke's law: $$F=-kx$$ Where F is the force exerted on the spring, x is the displacement of the spring from its eqilibrium position, and k is the spring constant. Simply re-arrange this law to get: $$k=F:(-x)$$
Since you know both x and F this problem should now become elementary.

anonymous · Answer

For the required work just use the common work equation: Work=Force*distance*cosine for the angle between the force and the distance

$$W=F*d*\cos \phi$$