Alberta Grade 8 Science – Light and Optical Systems Practice Test

Wavelength is the distance between adjacent crests. It’s a spatial measure of how long one complete cycle of the wave extends in space, telling you how far the wave travels before the pattern repeats. In light, the wavelength also relates to color—the visible spectrum ranges from shorter wavelengths (blue/violet) to longer wavelengths (red). The other terms describe different aspects: frequency is how many crests pass a point each second, period is the time for one complete cycle, and amplitude is how high the wave oscillates from rest. These describe timing and height, not the spacing between crests, so they don’t define the distance between adjacent crests.