Physics/Calculus
posted by Tim .
It takes a force of 21,714lb to compress a coil spring assembly on a New York City Transit Authority subway car from its height of 8in to its fully compressed height of 5in.
A. What is the assemblys force constant?
B. How much work does it take to compress the assembly the first halfinch? The second halfinch?

f = k x
21714 = k (3)
W = (1/2) k x^2
do for x = 1/2 inch
then for 1 inch and subtract the half inch result