Answer: Mechanical waves.
- A Electromagnetic waves
- B Mechanical waves
- C Matter waves
- D Transverse waves
Correct answer: B. Mechanical waves
Explanation: Mechanical waves (sound, waves on strings, water waves) need a medium to carry the disturbance. Electromagnetic waves can travel through vacuum, so they are not mechanical.
A standing wave forms from two identical waves travelling in opposite directions and interfering; nodes (always zero displacement) and antinodes (maximum displacement) stay fixed in place, unlike a travelling wave where the whole pattern moves.
Concept context
Wave types, superposition, standing waves, Doppler effect, and sound intensity.