SHM and Waves

  1.               Simple Harmonic Motion
    • 1.) Acceleration is directly proportional to displacement
    • 2.) Acceleration is always directed towards the equilibrium position.
    • 3.) Acceleration and displacement are in opposite directions.
  2. Vibrations can be:
    • Forced
    • Free
  3. Oscillation
    • to-and-fro movement.
    • Something which vibrates from side to side with a repeated cycle of motion
  4. Free vibration
    A vibration which vibrates at its own natural frequency
  5. Forced vibration / oscillation

    When an object is forces to oscillate at a particular frequency by an external oscillator giving it energy.
  6. Natural Frequency
    The frequency at which an object oscillates with greatest amplitude
  7. In any oscillating system there is a restoring force.
    What is a restoring force?
    The force which acts to drive the system back towards equilibrium position during an oscillation
  8. In an oscillating system including SHM there is constant interchange between ________ and ________ assuming there are no damping forces.
    Potential energy and Kinetic energy
  9. Damping forces
    Forces acting on an oscillating system that tend to reduce the total energy of the system

    (Friction at pivot or air resistance tend to reduce amplitude of system)
  10. Forced Frequency
    The frequency by which the driven system will oscillate at the frequency imposed by the driving agent
  11. Resonance
    When the frequency of a forced vibration is equal to the natural frequency of the vibrating object and thus creating a maximum amplitude.

    There is most efficient transfer of energy from outside to oscillating system
  12. Transverse Wave
    Oscillation of particles is perpendicular to the direction of wave motion
  13. Longitudinal Wave
    Motion of particle is parallel to wave direction
  14. Wavelength
    Distance between 2 adjacent points in phase
  15. Period
    Time taken for one oscillation to occur
  16. Amplitude
    The maximum displacement from the mean position
  17. Frequency
    The number of vibrations per second
  18. Progressive wave properties :
    • Wave profile moves with wave speed
    • Net transfer of energy along wave direction
    • Particles on same wave have the same amplitude
    • Adjacent particles are out of phase
  19. Stationary
    • Wave profile is static
    • No transfer of energy
    • Adjacent particles have different amplitudes: Nodes: Points of zero amp. Antinodes: Points of max amp
    • Adjacent particles are in phase
  20. Principle of superposition
    When two or more waves cross, the resultant displacement is equal to the sum of the individual displacement
  21. Constructive intereference
    Takes place when path difference is a whole number of wavelength
  22. Destructive Interference
    When path difference is one and a half wavelength
  23. Superposition is only possible when light is:
    • Coherent
    • ( Having a fixed phase difference )
  24. Monochromatic Light
    Light having a single wavelength ex.  sodium lamps and lasers
  25. What does Young's Double Slit experiment show?
    The effect of the principle of superposition. Bright and dark fringes are formed on screen due to destructive and constructive interference between the two overlapping waves.
  26. What does fringe separation depend on?
    • distance between slit S1 and S2 , d
    • Distance between double slit and screen, D
    • Wavelength of light
Card Set
SHM and Waves
Relating to Waves and simple harmonic motion.