Set your hand on fire or power a light bulb with lemons using these grade school experiments.

Wavelengths of light: Each hue in the visible spectrum has a corresponding wavelength measured in nanometers, which are only one billionth of a meter. Hue differences are tiny measurement differences between the crests of each wavelength. Red has the longest wavelength and violet the shortest.

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Seeing, hearing, feeling warmth, surfing, tuning the radio, using a cellphone – these and many more activities involve waves. But what is a wave? In this article, we get to grips with the different kinds of waves and look at the key characteristics of all waves – their wavelength, period, frequency, speed and amplitude. These concepts are important for describing waves of all kinds.

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