$A$ particle of mass $10 \text{ g}$ is executing simple harmonic motion with an amplitude of $0.5 \text{ m}$ and a periodic time of $(\pi / 5) \text{ s}$. The maximum value of the force acting on the particle is ... $N$.

The acceleration of a particle in $S.H.M.$ is

The weight suspended from a spring oscillates up and down. The acceleration of the weight will be zero at

The displacement of an oscillating particle varies with time $t$ (in seconds) according to the equation $y (cm) = \sin \left[ \frac{\pi}{2} \left( \frac{t}{2} + \frac{1}{3} \right) \right]$. The maximum acceleration of the particle is approximately ..... $cm/s^2$.

$A$ horizontal platform with a small object placed on it executes a linear $S.H.M.$ in the vertical direction. The amplitude of oscillation is $40 \text{ cm}$. What should be the least period of these oscillations, so that the object is not detached from the platform (in $\pi \text{ s}$)? [Take $g = 10 \text{ m/s}^2$]

The displacement of a particle moving in $S.H.M.$ at any instant is given by $y = a \sin \omega t$. The acceleration after time $t = \frac{T}{4}$ is (where $T$ is the time period).