a) Use Newton law to determine the force applied to the backrest when a 150-lb person leans 40% of his or her body weight against it. (Assume that there are no lever arms between the backrest and the spring to account for in this problem) the chair recline slightly. the design specifications call for deflection of no more than 2 inches.
b) Determine the constant requiered for the spring
c) Ii a 200lb person puts 70% of his body weight on the backrest, what spring extension would be expected ?(assume that the appied force is still within the alowable limits for the spring)