(adsbygoogle = window.adsbygoogle || []).push({}); If the phase angle for a block-spring system in SHM is φ and the block's position is given by x = xm cos(ωt+φ), what is the ratio of the kinetic energy to the potential energy at time t = 0? State your answers in terms of the given variables.

x =x_{m}Cos(wt + phi)

v = -w(x_{m})sin(wt +phi)

K = (1/2 mv^{2})

P = (1/2 m w^{2}x^{2})

dividing K/P= [v/wx]^{2}

substitute v and x we get: [(-w(x_{m})sin(wt +phi)/(w)(x_{m}Cos(wt + phi))]^{2}

simplifying we get:[-wtan(wt + phi)/w]^{2}= [tan(wt + phi)]^{2}

at t = 0 we should get the following: [v/wx]^{2}= [tan(phi)]^{2}

The answer is marked wrong, am I interpreting the question incorrectly? I know what ratio is.. and ratio for Kinetic energy and Potential should be K/P right?

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# Homework Help: Ratio for Kindetic and Potential energy

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