A teacher is planning for a class on simple pendulum with her students. She has a few materials A. Thin elastic string B. Light weight spring C. Cotton thread Which of the above materials can be chosen as the strings of a simple pendulum?

Option 4 : Only C

A simple pendulum is an ideal pendulum with a point mass hanging by a weightless inextensible fully flexible thread that can oscillate freely without friction.

A simple pendulum consists of a small metallic ball or a piece of stone suspended from a rigid stand by a thread. The metallic ball is known as Bob of the pendulum.

• The to and fro motion of the simple pendulum is an example of periodic or oscillatory motion.
• For setting up a simple pendulum we should use the inextensible material so, the teacher can use a cotton thread.
• The simple pendulum can be built by tying a one-meter long thread to a small metal ball and suspending it from a sturdy support, allowing the Bob to swing freely. The Bob of the pendulum is in the mean position when it is at rest.

Hence, we conclude that the teacher can use cotton thread as the strings of a simple pendulum.

HintSpring cannot be used for making the string of a simple pendulum as it is extensible.