vibration

• someone can speak because the air particle is vibrating
• vibration/oscillation is a periodic motion in which an object moves back and forth repeatedly about the equilibrium positiob
• a complete cycle of a vibration occurs when the force is applied and the load swings from point A-B-C-B-A
• the properties of vibration: amplitude, period and frequency
• period is the time taken to complete one full cycle of vibration
• frequency is the number of cycles per second or hertz (Hz)
• amplitude is the maximum displacement of an object from its equilibrium position
• when a particle vibrates, the distance in any direction from the equilibrium position is called displacement
• the unit of period is seconds (s)
• the unit of frequency is hertz (Hz)
• a pendulum makes 100 oscillations in 25 s. Find the period and the frequency of the pendulum. the frequency is 4 Hz and the period is 0.25 S