Question

5- Hooke’s law describes a certain light spring of unstretched length 35.0 cm. When one end is attached to the top of a doorframe and a 7.50 kg object is hung from the other end, the length of the spring is 41.5 cm. (a) Find its spring constant. (b) The load and the spring are taken down. Two people pull in opposite directions on the ends of the spring, each with a force of 190 N. Find the length of the spring in this situation.

Answer 1

Answer:

Explanation:

      a)     kx = mg in first case

              k (6.5) = 75

               k= 11.5

b)  2 (190) = (1/2 ) k (2x)²  where x is extension on each side

     simplify u will get x = 4 (approx)

    hence the new length = 35 + 2x = 35+8 =43cm