Properties of Wave Pulses and Waves
▶︎ Watch it animatedinteractive step-through · ~3 min · optional ⚙︎ Open the appletPulse Bench · run a pulse the length of the rope and read the tagged particle's trail against the distance the pulse coveredA wave transports energy between two locations while the medium stays put: each particle oscillates about its own equilibrium position and goes nowhere, so the cork bobs in place and the air molecule near a speaker moves back and forth about a fixed spot. A wave is transverse or longitudinal according to the direction a single particle moves relative to the direction of travel, which makes sound longitudinal however it is drawn. The speed of a mechanical wave is fixed by the medium, $v = \sqrt{F_T/(m/L)}$ on a string, so nothing the source does can change it.
Three errors dominate. Picturing the medium itself travelling with the wave, so air drifts across the room toward a listener. Calling a wave transverse because the drawing looks like a sine curve, without asking what the vertical axis plots or which way the particles actually move. And treating the wave speed as something the source controls, so shaking a rope harder or shouting louder is expected to speed the wave up, when those change the amplitude and the frequency and leave $v$ alone.
The work
3 ways in · any order
Lesson
Properties of Wave Pulses and Waves
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Keeps the medium oscillating in place while the energy travels, classifies a wave from the motion of one particle rather than the shape of the graph, and hands the wave speed to the medium rather than the source.
Diagnostic
10-item topic check
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Ten items spanning the failure modes of this topic: carrying the medium along with the wave, reading transverse off a sine-shaped drawing, and letting a louder or faster source speed the wave up. Take it cold to find which one is yours, or after the lesson to confirm it is not.
Targeted Practice
Drill a single misconception
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Pick one of the failure modes you missed and drill it on its own. The round is adaptive: two correct in a row clears it for now and moves you to the next. Two in a row is a checkpoint, not proof: if the error resurfaces later, the misconception comes back.