# mechanical wave

## types of mechanical waves

There are three types of mechanical waves: transverse, longitudinal, and surface waves. They differ in how particles of the medium move. You can see this in the Figure 1.1. In a transverse wave, particles of the medium vibrate up and down perpendicular to the direction of the wave. In a longitudinal wave, particles of the medium vibrate back and forth parallel to the direction of the wave. In a surface wave, particles of the medium vibrate both up and down and back and forth, so they end up moving in a circle. Q: How do you think surface waves are related to transverse and longitudinal waves? A: A surface wave is combination of a transverse wave and a longitudinal wave.

## the medium

The energy of a mechanical wave can travel only through matter. The matter through which the wave travels is called the medium (plural, media). The medium in the water wave pictured above is water, a liquid. But the medium of a mechanical wave can be any state of matter, even a solid. Q: How do the particles of the medium move when a wave passes through them? A: The particles of the medium just vibrate in place. As they vibrate, they pass the energy of the disturbance to the particles next to them, which pass the energy to the particles next to them, and so on. Particles of the medium dont actually travel along with the wave. Only the energy of the wave travels through the medium.

## waves in matter

The waves in the picture above are examples of mechanical waves. A mechanical wave is a disturbance in matter that transfers energy through the matter. A mechanical wave starts when matter is disturbed. A source of energy is needed to disturb matter and start a mechanical wave. Q: Where does the energy come from in the water wave pictured above? A: The energy comes from the falling droplets of water, which have kinetic energy because of their motion.

## instructional diagrams

No diagram descriptions associated with this lesson

## questions

types of mechanical waves include

``````a) transverse waves.

b) longitudinal waves.

c) surface waves.

-->  d) all of the above
``````

mechanical waves can travel through liquids and gases but not through solids.

``````a. true

-->  b. false
``````

particles of the medium actually travel along with a mechanical wave.

``````a. true

-->  b. false
``````

in which type of wave do particles of the medium move in small circles?

``````-->  a) surface wave

b) transverse wave

c) longitudinal wave

d) none of the above
``````

a longitudinal wave is a combination of a transverse wave and a surface wave.

``````a. true

-->  b. false
``````

## diagram questions

No diagram questions associated with this lesson