The motion of a block-spring system is described by x(t) = A sin(ùt). Find ù, if the potential energy equals the kinetic energy at t = 6.11 s.

I'm really not sure how to solve this. It seems that you need more information, either x or A? I appreciate any help, thank you!

2 answers

Potential eneregy equals kinetic energy in a simple-harmonic-motion system when the phase angle (measured from the zero-deflection position) is pi/4 radians (or 3 pi/4 or 5 pi/4 or 7 pi/4)

If 6.11*ù = pi/4, then
ù = 0.1285 s^-1 is one possibility
Thank you for your help!