In a room that is 2.19 m high, a spring (unstrained length = 0.38 m) hangs from the ceiling. A board whose length is 1.60 m is attached to the free end of the spring. The board hangs straight down, so that its 1.60-m length is perpendicular to the floor. The weight of the board (110 N) stretches the spring so that the lower end of the board just extends to, but does not touch, the floor. What is the spring constant of the spring? I know that I'm suppose to use the equation F applied = Kx an find the spring constant K by changing the formula to K= F/X but I'm just wondering how I can interepret the displacement of the spring in this problem. The last sentence of the problem confused me a little bit that since the board can extend to but does not touch the floor does that mean that I can subtract the unstrained length .38 m from the length of the room and use that as my X or do I had to factor in the 1.60 m as well? Thanks for all ur help.