Key Terms
Period (T)
Time for one full wave cycle. Units: seconds.
Frequency (f)
Number of oscillations per unit time. Units: Hz.
SHM
Oscillatory motion where the net restoring force follows Hooke's law (F = -kx). No damping.
Amplitude (A)
Maximum displacement from equilibrium.
Displacement
X(t) = A cos(2*pi*t/T) Velocity: v(t) = -v_max * sin(2*pi*t/T) Acceleration: a(t) = -(k/m) * A * cos(2*pi*t/T)
Total mechanical energy is constant (no damping)
E_total = KE + PE = (1/2)mv^2 + (1/2)kx^2 = constant
Remember
UNDERdamped means the system is NOT damped enough, so it OVERSHOOTS and oscillates. OVERdamped means there is TOO MUCH d
Less damping
Taller, narrower resonance peak. More selective.
Wavelength (lambda)
Distance between adjacent identical points. Wave velocity (v): speed of disturbance propagation.
Wave velocity (v)
Speed at which the disturbance propagates. Units: m/s.
Node
Point of zero displacement in a standing wave. The string (or medium) does not move here.
Antinode
Point of maximum amplitude in a standing wave. Located midway between nodes.
Beat frequency
F_beat = |f_1 - f_2|
Wave energy is proportional to amplitude squared
E proportional to A^2
Intensity (I)
Power per unit area. Units: W/m^2.