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be aware of large trucks on the roadway
Tip: usually, these signs are hazard signs or warning.
Also, this isnt physics </span><span />
Answer:
The boundaries cause the waves to change direction an effect called <u>refraction.</u>
Explanation:
When a wave crosses a boundary between different materials, the speed of the wave and its wavelength changes.When passing from air to water the two properties (speed and wavelength) decreases, and the wave is observed to change direction as it crosses the boundary between the two material.The bending of the wave is called refraction.
Atmospheric refraction is the deviation of light or other electromagnetic wave from a straight line as it passes through the atmosphere due to the variation in air density as a function of height. ... Refraction not only affects visible light rays, but all electromagnetic radiation, although in varying degrees.
So in short, the answer is D.
(My answer got deleted because it didnt explain which is dumb)
They help scientists explain concepts that are difficult to observe.