Talha's Physics Academy: Q. Define Simple Pendulum. Describe its working and write formula for its Time Period.

SIMPLE PENDULUM:

An ideal simple pendulum consists of a point mass suspended from a light inextensible string tied to a grid and friction less support when the bob of the pendulum is vertical, the gravitational force F_G acts vertically downward and the tension T acts vertically upwards in this case the force F_G is balanced by the tension ‘T’ in the string. When the bob is slightly displaced from its mean position, it beings to perform oscillatory motion.

Forces acting on the bob in simple pendulum At the mean position 0, a pendulum is in its equilibrium position. If no external force were applied, the bob of a pendulum would naturally settle here as illustrated in fig. The curve path s is the distance the bob of a pendulum travels. The weight mg consists of the components mg cosθ along the string and mg sine perpendicular to the arc. For each given string, the component mg cosθ perpendicular to the string is exactly cancelled by the tension in the string. The resulting net force, which is directed back toward the equilibrium point, is tangential to the arc and equals mg sinθ