Follow a disturbance as energy travels without carrying the medium along with it.
Use the model, then answer without looking back. Each check isolates one decision a learner should be able to make after this lesson.
A source oscillates. The source sets the frequency f, the number of crests launched each second.
The relation v=fλ is exact for a single-frequency wave once the medium's propagation speed is defined. Superposition lets many such waves form a richer pattern.
The medium's particles oscillate locally while the disturbance carries energy along the medium. A wave is a pattern in motion, not a chunk of matter traveling from source to receiver.