The velocity of a particle executing a simple harmonic motion is 13 ms^$$-$$1, when its distance from the equilibrium position (Q) is 3 m and its velocity is 12 ms^$$-$$1, when it is 5 m away from Q. The frequency of the simple harmonic motion is

A uniform string of length L and mass M is fixed at both ends while it is subject to a tension T. It can vibrate at frequencies (v) given by the formula (where n = 1, 2, 3, ....)

A particle vibrating simple harmonically has an acceleration of 16 cms^$$-$$2 when it is at a distance of 4 cm from the mean position. Its time period is