====== Sonometer with Suspended Weights ====== {{:physicsdemos:waves_and_optics:instruments:sonometer_with_suspended_weights.jpg?400|}} Two metallic strings with different mass densities are stretched across a pair of bridges on a cavity resonator. One end of each string is attached to a weight pan and hung over a pulley to provide an adjustable and known tension to the string. Mersenne's laws may be demonstrated by observing the change in frequency as a function of tension, string length, and density. L2 PIRA DCS 3D20.10