An endoscope uses glass fibres to enable doctors to 'see' inside a person - Edexcel - GCSE Physics - Question 5 - 2015 - Paper 1
Question 5
An endoscope uses glass fibres to enable doctors to 'see' inside a person.
Complete the sentence by putting a cross (X) in the box next to your answer.
Rays of lig... show full transcript
Worked Solution & Example Answer:An endoscope uses glass fibres to enable doctors to 'see' inside a person - Edexcel - GCSE Physics - Question 5 - 2015 - Paper 1
Step 1
Complete the sentence by putting a cross (X) in the box next to your answer.
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Answer
The correct answer is C total internal reflection. This is the principle that allows light to be guided through the optical fibres without escaping, making it essential for the functioning of endoscopes.
Step 2
Complete the diagram to show the path of the ray of light inside the glass block.
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Answer
In the diagram, the ray of light should enter the glass block at the curved surface at an angle. As it enters the block, it will reflect off the flat bottom surface at an angle greater than the critical angle, ensuring that total internal reflection occurs. Draw the incoming ray from the ray box striking the curved surface, and then reflect it off the flat base.