A 0.12 kg block on a horizontal frictionless surface is attached to a spring whose force constant is 570 N/m.

A 0.12 kg block on a horizontal frictionless surface is attached to a spring whose force constant is 570 N/m. The block is pulled from its equilibrium position at x = 0m to a displacement x = +0.080m and is released from rest. The block then executes simple harmonic motion along the x-axis (horizontal). What is the displacement of the block at time t=0.20s?

a,-0.01m
b.-0.08m
c.0.01
d.0.1
e.0.08

ω = √(k / m)
ω = √(570 / 0.12)
ω ≈ 68.9 rad/s

x = x_max*cos(ωt + φ)
x = 0.080*cos(68.9t)
x(0.20) = 0.080*cos(68.9*0.20)
x(0.20) = 0.0280 m