Question

Explain the terms amplitude, frequency and phase of a wave.

Short answer

Amplitude is the maximum displacement from equilibrium. Frequency is the number of cycles per second. Phase is the position within the wave cycle.

Step-by-step solution

- Define Amplitude

The amplitude of a wave is the maximum displacement of points on a wave, measured from the wave's equilibrium position. It represents the wave's height and is a measure of the energy carried by the wave. Higher amplitude means higher energy.

- Define Frequency

The frequency of a wave is the number of oscillations or cycles that occur in a specific period, typically one second. It is measured in Hertz (Hz). Frequency often determines the pitch of a sound wave or the color of a light wave.

- Define Phase

The phase of a wave describes its position within a cycle at a given point in time. It is often measured in degrees or radians. Phase indicates where a point is along the wave in relation to the start of the cycle, with 0 or 360 degrees indicating the start and end of a cycle, respectively.

Key concepts

Amplitude

Amplitude is a fundamental property of a wave. It refers to the maximum distance that the particles of the medium move from their rest position due to the wave. Think of it as the wave's height. If you imagine a wave moving in the ocean, the amplitude is the height from the calm sea level (equilibrium position) to the crest (top) of the wave. Higher amplitude means that the wave carries more energy. For instance, in sound waves, a higher amplitude results in a louder sound. Similarly, in light waves, increased amplitude means a brighter light. Always remember that amplitude is a key measure of the energy within the wave.

Frequency

Frequency is another essential characteristic of a wave. It is defined as the number of cycles that occur in a unit of time, usually one second. This measure is expressed in Hertz (Hz). To visualize, consider a wave in the sea again; if you count how many complete waves (from crest to trough and back) pass a point in one second, you’ve measured the wave’s frequency. Frequency is crucial in different types of waves. For example, in sound waves, a higher frequency means a higher pitch. In light waves, it affects the color perceived by us. A frequency of more cycles per second translates to a blue color, while fewer cycles result in a red color.

Phase

The phase of a wave is an interesting concept that describes the position of a point along the wave cycle at a specific time. The phase is usually measured in degrees or radians. If we break down a single cycle of a wave into a circular motion, 0 or 360 degrees mark the start and end of the cycle, respectively. By understanding the phase, one can determine where a wave's current position is in relation to its starting position. When we talk about the phase shift between two waves, it means that the waves are out of sync by some angle. This is crucial in many areas, such as signal processing and telecommunications, where wave phases affect how signals are perceived and interpreted.