Q1: The motion of a particle moving with S.H.M. from an extremity to the other, constitutes

ANS:A - half an oscillation

Half an oscillation refers to the motion of a particle in a simple harmonic motion (S.H.M.) from one extreme position (maximum displacement) to the central position (equilibrium position) or from the central position to one extreme position. In a simple harmonic motion, the particle oscillates back and forth around its equilibrium position. The motion of the particle is periodic, meaning it repeats itself at regular intervals. A complete oscillation comprises the particle's motion from one extreme position, through the equilibrium position, to the other extreme position, and back to the equilibrium position. This encompasses the entire cycle of motion. However, a half oscillation involves only half of this motion, either from one extreme to the equilibrium position or from the equilibrium position to one extreme. For instance, if you push a pendulum bob to its highest point, then release it, it swings down to the equilibrium position, and this motion constitutes half an oscillation. Likewise, if the pendulum is initially at its equilibrium position, and you pull it to one side, it swings to the opposite side, which again constitutes half an oscillation. Understanding half oscillations is essential in analyzing periodic motion and understanding the behavior of systems undergoing simple harmonic motion.