Question

Oscillatory motion can be defined as a motion that is repeated over and over. With no friction, the motion would continue forever. Oscillatory motion can be found throughout the world. Think of something you know of in everyday life, other than a pendulum, that exhibits oscillatory motion. Address the following:

• Describe the item that exhibits this motion.
• Explain whether it is simple harmonic motion.
• Is it a damped oscillator, or is it driven?
• Explain, if applicable, why it was designed to undergo simple harmonic motion

Answer 1

I will take Bungee jumping cord as an example.

As we all know bungee jumping cord is highly elastic and a jumper is attached to one of its end. When released from a great height, the jumper will fall under the effect of gravity and at the lower most point, jumper will bounce back up in the air. This process will continue until the resistive forces from air dominate the force of elasticity. The bungee cord will oscillate up and down.

Here, this motion is damped motion because there is an air friction acting on the jumper and cable. Due to this damping, the amplitude will keep on decreasing before finally becoming zero. Ideally, if motion is not damped, the jumper will keep on moving up and down forever.

Here, The Bungee Jumping motion is a type of vertical Simple Harmonic Motion. After the jump, jumper is in free-fall and soon when he/she reaches the maximum extension of the rope, his/her speed will be zero. The restoring force applied by the rope will cause to rebound and continue to oscillate