The tuning fork has a frequency 120 Hz. A hanging mass M is creating the tension needed to create the standing wave pattern shown in the picture above. The magnitude of M is such that the standing wave pattern has four antinodes or "loops." The string from the tuning fork to the point where the string touches the top of the pulley has a length of 1.20 m. The linear density of the string is 1.0 x 10-4 kg/m, and remains constant throughout.