Small lighting knowledge | stood on the Banks look at the bottom, feel the bottom of the river than the actual deep or shallow? - China lighting network

Eyes see things in water or other medium, see is a virtual image of the object, not the actual object, which is caused by the refraction. Light propagation in the air speed is about 300000 km/s ( Kilometers per second) And spread in the glass, water or other transparent objects, its speed is obviously decreased. The light from the first into the second medium medium, two kinds of different medium, the speed of light is different, different incident Angle and the Angle of refraction. Stood on the Banks of the river at the bottom, the light is spread in the air slowly in the water, light waves by a medium into another medium refraction will happen. As people see in the bank to the water, at this time, people to see the bottom of the river is, in fact, the virtual image formed by the refraction of light, so by the shore into the water, virtual image than the actual bottom of the river. By the water to the shore, virtual image is higher than the actual object position, can vividly called 'shallow people look at fish, fish at high'. YanZhiXiang

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