unit 1 lesson 1 oscillatory motion

• the motion is divided into

  periodic motion and tranlversal motion
• Periodic motion is a regularly repeated motion at equal periods of time
• periodic motion is divided into

  oscialtory motion and wave motion
• define Oscillatroy motion

  it is a motion that is regularly repeated at equal periods of time sides of its rest point
• examples of oscillatory motion

  spring , pendulum, stretched strings, tuning fork
• give reason for: although the motion of the rotary bee is considered as a periodic motion, but not as an oscillatory motion

  because it is repeated at equal periods of time but not on both sides of rest position
• the simple harmonic motion is considered the simplest form of oscillatory motion
• properties of oscillatory motion are considered as 4 things:

  1. amplitude
  2. complete oscillation
  3. periodic time
  4. frequency
• define the amplitude

  is the maximum displacement done by an Oscillating body away from its position
• the measuring unit of the amplitude is centimeter or meter
• define the complete oscillation

  is the motion of an oscillatory body when it passes by a fixed point on its path two successive times in the same direction
• the one complete oscillation= 4x amplitude
• law of kinetic energy

  $1/2 x mass x velocity 2$
• define periodic time

  it is the time taken by an oscillating body to complete one oscillation
• periodic times unit is seconds
• what is the law of periodic time

  periodic time= time/no. of c.osc
• define frequency

  is the number of complete oscillations in one second
• frequency is measured in hertz
• law of frequency

  frequency= no. of complete oscillations/time
• the frequency is inversely proportional to periodic time

  the frequency is reciprocal to the periodic time
• answer equation: if an oscillating body make 480 complete oscillations in one minute, calculate frequency and periodic time

  $frequency=$$no. of c.osc/time =$$480/60 =$$8 hz$
• what is meant by: the maximum displacement made by a oscillating body is 6 cm 


  this means that the amplitude of the oscillating body= 6cm
• what is meant by: the amplitude of the oscillating body= 0.2 meter

  this means that the maximum displacement of the oscillating body= 0.2 meters
• what is meant by: complete oscillation

  it is the motion of the oscillating body when it passes by a fixed point two successive times in the same direction
• what is meant the periodic time of a tuning fork is 0.5 seconds

  this means that the time taken by the oscillating body to complete one complete oscillation is 0.5 seconds
• give reason for: the oscillatory motion is considered as periodic motion?

  because it is the motion that is regularly repeated at equal periods of time
• give reason for: the motion of the spring is considered oscillatory motion

  because it the motion that is regularly repeated at equal periods of time on both sides of its rest point