Question
Describe the energy transformation taking place in an oscillating pendulum.
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Answer
When a pendulum swings to$-$and$-$fro, its energy is constantly from potential to kinetic and vice$-$versa. Let us consider the energy transformation in the pendulum at its different positions. At position $B,$ when the bob is raised from position $A$ to position $B$, the work is done on it against the force of gravity. This work done gets stored in it in the form of gravitational potential energy. At this position, the pendulum has only potential energy but no kinetic energy.
At position $A,$ when the bob starts moving down from position $B$ to position $A$, its potential energy goes on decreasing but its kinetic energy goes on increasing. When the bob reaches the mean position $A$, it has only kinetic energy but no potential energy.
At position $C$, as the bob goes from position $A$ towards $C$, its kinetic energy goes on decreasing but its potential energy goes on increasing. On reaching the extreme position $C$, the bob has only potential energy but no kinetic energy.
At position $A,$ when the bob starts moving down from position $B$ to position $A$, its potential energy goes on decreasing but its kinetic energy goes on increasing. When the bob reaches the mean position $A$, it has only kinetic energy but no potential energy.
At position $C$, as the bob goes from position $A$ towards $C$, its kinetic energy goes on decreasing but its potential energy goes on increasing. On reaching the extreme position $C$, the bob has only potential energy but no kinetic energy.
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