Oscillations, waves and superposition Flashcards
oscillation
an oscillation is a to-and-fro motion between two limits
free oscillations
free oscillations are oscillations with constant amplitude without energy loss or gain as there is no driving or resistive forces acting on it
Simple harmonic motion
Simple harmonic motion is a type of oscillatory motion where the acceleration is:
directly proportional to displacement from the equilibrium position and directed opposite to displacement
natural frequency
natural frequency is the frequency at which a body will vibrate when there are no driving or resistive forces acting on it
damped oscillations
damped oscillations are oscillations in which the amplitude decreases with time as a result of dissipative forces that reduce the total energy of the oscillations
forced oscillations
forced oscillations are oscillations where there is constant input of energy by external periodic force that maintains the oscillations amplitude
Principle of Superposition
when two or more waves overlap at a point, the resultant displacement is the sum of the individual displacements of each wave at that point
Constructive interference
constructive interference occurs when two or more waves meet at a point such that the resultant displacement is larger then the largest individual displacement
Formation of stationary wave
a stationary wave is formed when 2 progressive waves of the same type, amplitude, frequency, wavelength and speed travelling in opposite direction overlap and superpose
diffraction
diffraction is a phenomenon where a wave spreads out after passing through a slit or around the edge of an obstacle
Coherence
Sources are said to be coherent if they produce waves that have a constant phase difference
Rayleigh criterion
Rayleigh criterion states that when the two objects are just resolved, they can be distinguished and this happens when the first minimum of the diffraction pattern of one source coincides with the central maximum of the diffraction pattern of the other source
