Answer:
Mechanical waves
Step-by-step explanation:
Waves are classified into two types:
- Electromagnetic waves: these waves are oscillations of the electric and magnetic fields in a direction perpendicular to the motion of the wave. They all travel at the speed of light in a vacuum, and they are the only waves able to travel through a vacuum. Examples of electromagnetic waves are visible light, radio waves, microwaves..
- Mechanical waves: these waves are produced by the oscillations of the particles in a medium. Due to their nature, they cannot travel in a vacuum, since there is no medium. Examples of mechanical waves are: sound waves, seismic waves, etc.
In this problem, the tuning fork is struck against a hard surface; as we know, the particles in the tuning force begin to vibrate quickly, causing vibrations in the particles in the air. These are sound waves: sound waves are mechanical waves (because they are produced by the vibrations of the particles in the medium), therefore the correct answer is
Mechanical wave