Wave Graphs

Waves may be graphed as a function of time or distance. A single frequency wave will appear as a sine wave in either case. From the distance graph the wavelength may be determined. From the time graph, the period and frequency can be obtained. From both together, the wave speed can be determined.

Any of the wave parameters below can be changed. When you have finished entering data, click on the quantity you wish to calculate. The quantities will not be forced to be consistent until you click on the desired quantity. Wavelength = m Frequency = Hz Period = s Amplitude = 2 Wave velocity = m/s 波长 = m 频率 = Hz 周期 = s 幅度 = 2 波速 = m/s 中文译文中的待填/计算数值依次对应：1：w 2：f 3：t 4：v。实际数值以上方原输入框为准。 以下任意一个波参数都可以被改变。在输入完数据后，点击你希望计算的量。直到你点击所需的量之前，这些量不会被强制保持一致。

Traveling Waves

Elasticity and a source of energy are the preconditions for periodic motion, and when the elastic object is an extended body, then the periodic motion takes the form of traveling waves.

	A pond has an equilibrium level, and gravity serves as a restoring force. When work is done on the surface to disturb its level, a transverse wave is produced. 池塘有一个平衡水位，重力作为恢复力。当对表面做功以扰动其水位时，会产生横波。
	A disturbance of the air pressure at a single point produces a spherical traveling pressure wave (sound). A sound wave in air is a longitudinal wave. 在空气中的一个点上产生的气压扰动会形成一个球面传播的声波（sound）。在空气中，声波是一种纵波。

Waves on a Pond

A pebble thrown into a pond will produce concentric circular ripples which move outward from the point of impact. If a fishing float is in the water, the float will bob up and down as the wave moves by. This is a characteristic of transverse waves. Such waves obey the wave relationship. 当一块鹅卵石投入池塘时，会形成向外扩散的同心圆波纹。如果水中有一个鱼漂，波纹经过时鱼漂会上下浮动。这是横波的一个特征。这类波遵循波的关系式。

This is an example of the transverse waves produced by bubbles rising from the bottom of this clear pool along the Icefields Parkway in Alberta, Canada. Although not exactly a circle, and not exactly a sine wave, these ripples show the tendency of surface disturbances to produce traveling waves in all directions from the source.

The form of the dependence of the traveling wave parameters upon each other is a consequence of the basic motion equation and the definitions of the the terms which describe periodic motion. The description of water waves above is greatly oversimplified to demonstrate the nature of sinusoidal transverse waves. Waves on the ocean are much more complex, involving a circulation of the water as the wave passes so that the actual water motion is not just simple harmonic motion.