1. The problem statement, all variables and given/known data The figure shows a block on a frictionless surface attached to a spring. The block is pulled out to position x_i = 20 cm, then given a "kick" so that it moves to the right with speed v_i. The block then oscillates with an amplitude of 44 cm. Image of the problem - http://session.masteringphysics.com/problemAsset/1013861/11/jfk.Figure.Q14.21.jpg What is the oscillation frequency? What is the total mechanical energy of the oscillator? What was the initial speed v_i? 2. Relevant equations Hooke's Law Force = k*change in distance Frequency - (1/2*pi)*sqrt(k/mass) Total mechanical energy = potential energy + kinetic energy Potential energy = 1/2*k*Amplitude^2 Kinetic energy = 1/2 * mass*v_max^2 3. The attempt at a solution F=k*change in x 20 = k*0.2 k = 100 Frequency= (1/2pi) * sqrt(k/m) Frequency=(1/2pi) * sqrt (100/.5) Frequency=2.251 Hz For some reason the answer is 1.0 Hz but I can't figure out what I did wrong. Once I figure this one out I can move onto the next two.