Amplitude (A), Period (T) and Frequency (N) of S.H.M.

A particle performs linear SHM with amplitude A and frequency n. Its speed midway between an extreme position and equilibrium position is ______.

A mass M attached to a horizontal spring executes S.H.M. of amplitude A₁. When the mass M passes through its mean position, then a smaller mass m is placed over it and both of them move together with amplitude A₂. The ratio of `(A_1/A_2)` is ______ 

Two trains are moving towards each other with speeds of 20m/s and 15 m/s relative to the ground. The first train sounds a whistle of frequency 600 Hz. The frequency of the whistle heard by a passenger in the second train before the train meets, is ______. (the speed of sound in air is 340 m/s) 

A needle of a sewing machine moves along a path of amplitude 4 cm with a frequency of 5 Hz. Find its acceleration `(1/30)` s after it has crossed the mean position.

A particle performing S.H.M. has velocities of 8 cm/s and 6 cm/s at displacements of 3 cm and 4 cm respectively. Calculate the amplitude and period of S.H.M.

A simple pendulum moves from one end to the other in ¼ second. What is its frequency?

What is the amplitude of S.H.M. 

A particle performing SHM starts equilibrium position and its time period is 16 seconds. After 2 seconds its velocity is π m/s. Amplitude of oscillation is ______. `(cos 45° = 1/sqrt2)`