True or False. When light passes from one medium to another the speed stays constant

The speed of light is not the same across different medium because of different refractive index. The correct answer is False

The speed of light is approximately 300000000 m/s in a vacuum.

This speed is not the same across different medium because of different refractive index of different medium. Light travels at approximately 300000000 m/s in a vacuum at refractive index of 1

The refractive index of water is about 1.3 which will eventually limit the speed of light. Likewise, the refractive index of glass is about 1.5. This will further reduce the speed at which light travels.

It is therefore False to say that : When light passes from one medium to another the speed stays constant

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