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Question
What device other than a plane mirror can be used to turn a ray of light through 180°? Draw a diagram in support of your answer. Name an instrument in which this device is used.
Solution
A total reflecting prism can be used to turn a ray of light by 180°. The following diagram can make it further clear.
This action of prism is used in binocular.
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RELATED QUESTIONS
Copy the diagram given below and complete the path of the light ray till it emerges out of the prism. The critical angle of glass is 42°. In your diagram mark the angles wherever necessary.
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