Waves carry energy along the path displacing the matter for a brief period. However, the matter does not travel along the wave and instead will return to its natural rest position once the wave moves past it. For example, an ocean wave can travel many miles without displacing the entire ocean.

Transverse waves are waves whose particles travel perpendicular to the direction that the wave itself is traveling. Electromagnetic waves are another example of transverse waves.

The relationship between wavelength and frequency is given by the equation  where  is the wavelength,  is the speed of light, and  is frequency.

We are given the values for frequency and the speed of light, allowing us to solve for the wavelength.

Electromagnetic waves all travel at the same speed which is the speed of light.  The speed of light in a vacuum is nearly 

Electromagnetic waves are the only type of wave that does not require a medium to travel. Light, radio, and microwaves are examples of electromagnetic waves. Sound does require a medium to travel. In a vacuum, soundwaves cannot travel as there is no air to compress.

Longitudinal waves are waves whose particles travel parallel to the direction that the wave itself is traveling. Sound waves are another example of longitudinal waves.

The speed of the wave along the Slinky depends on the mass of the Slinky itself and the tension caused by stretching it. Since both of these things have not changed, the wave speed remains constant.

The wave speed is equal to the wavelength multiplied by the frequency.

Since she is moving her hand faster, the frequency has increased. Since the velocity has not changed, an increase in the frequency would decrease the wavelength.

Sound is often described in terms of the vibration of the molecules of the medium in which it travels (in other words, the displacement of the molecules). Sound can also be viewed from a pressure point of view because this variation in pressure is easier to measure. In compression, the pressure is higher because the molecules are closer together. In rarefaction, there is an expansion of molecules and, therefore, a lower pressure.

When you see a relationship like "times every second" or "once per hour," these are hints you are looking at a frequency. Frequency is, effectively, how often something happens. If it happens four times per second, then we know how often it happens. The units "per second" are equivalent to Hertz.

The relationship between frequency and period is .

Since our given frequency was four beats per second, or , we can solve for the period.

This means that her heart beats once every 0.25 seconds.

The relationship between wavelength and frequency is given by the equation , where  is the wavelength,  is the speed of light, and  is frequency.

We are given the values for frequency and the speed of light, allowing us to solve for the wavelength.