A long, light string is tied to a much heavier string under the same tension and stretched horizontally across a laboratory bench. A single, narrow gate located several meters beyond the junction admits only displacements that lie in a line making an angle of 30° with the vertical; any other component is blocked.
A short, upward (positive) transverse pulse of amplitude 5 cm and frequency 4 Hz travels along the light string toward the junction and then continues toward the gate.
(a) Describe whether the pulse reflected at the junction will be inverted or non-inverted, and explain the physical reason for your answer.
(b) Explain how the frequency and wavelength of the pulse in the heavier string compare with those in the light string. Justify your reasoning.
(c) After the transmitted pulse passes through the narrow gate, qualitatively describe how its intensity compares with that immediately before the gate, and account for the change.