Two springs, each with unstretched length 0.200 m, but with different force constants k1 and k2, are attached to opposite ends of a block with mass m on a level, frictionless surface. The outer ends of the springs are now attached to two pins P1 and P2, 0.100 m from the original positions of the ends of the springs (the figure ). Let k1 = 2.00 N/m , k2 = 6.40 N/m, and m = 0.100 kg .
Find the length of each spring when the block is in its new equilibrium position after the springs have been attached to the pins.
I got this part, L1=.352 m and L2=.248 m
Find the period of vibration of the block if it is slightly displaced from its new equilibrium position and released.
The Attempt at a Solution
I was given m, but I did not know what to use for k. I know how to find the k for springs in a series, but not when they are separated and acting in opposite directions. Any help is greatly appreciated!