Which of the following statements are correct of the production and propagation of waves? I. vibration…

Analyze the question: We need to decide which of the four statements correctly describe how waves are produced and how they propagate.

Concept: A wave is a disturbance that transfers energy from one point to another. The particles of the medium only oscillate about their mean positions. They do not travel along with the wave.

Checking each statement:

• I. Vibration produces waves. This is correct. A vibrating source (a plucked string, a tuning fork, a vibrating finger in water) creates a disturbance that spreads out as a wave.
• II. Waves transmit energy along the medium. This is correct. The main job of a wave is to carry energy from one place to another.
• III. The medium does not travel with the wave. This is correct. Water particles move up and down as a ripple passes, but the water does not move across the pond with the ripple.
• IV. Waves do not require any medium for transmission. This is not correct as a general statement. Mechanical waves such as sound and water waves need a medium. Only electromagnetic waves (light, radio waves) can travel through a vacuum. Since the question speaks of waves in general, IV cannot be called correct.

So the correct statements are I, II and III only.

Exam tip: Whenever a statement says "waves do not require any medium", be careful. It is true only for electromagnetic waves. For general wave statements, remember: waves carry energy, not matter. Statements containing absolute claims like "do not require any medium" are often the wrong ones in JAMB.