Simple harmonic motion is closely related to a uniform circular motion.
A real life simple harmonic motion.
Review Question 1
Answer the following questions as you watch the first YouTube video(Simple harmonic motion and uniform circular motion).
- How does the centre of the red cylinder and the green ball relate?
- At which part of the SHM(left) is the red cylinder moving the fastest and slowest?
- At which part of the circular motion(right) is the green ball moving vertically the fastest and slowest?
Review Question 2
Navigate to this site. This animation shows how a 4-stroke engine internal combustion works.
Answer the following questions:
- The piston is moving with SHM. At which point is the piston the fastest?
- At which point is the piston moving the slowest?
Given that the maximum velocity of the piston is ,
- write down the expression of the velocity of the piston at the position shown in the diagram.
- write down the expression of the acceleration of the piston at the position shown in the diagram.
- Sketch a velocity-time graph of the SHM demonstrated by the piston. Draw two complete cycles and label the parts A, B and C on your graph.