08 Feb Total Internal Reflection
Did you know that Colon Cancer is the most common cancer across Singapore, according to the Ministry of Health? A precursor for Colorectal Cancer is adenomatous polyps, which are benign lumps on the inner wall of the intestines, colon and rectum. Although they are benign, there is a chance that adenomatous polyps in the colon or rectum may transform into cancer. If such polyps are detected, they should be removed to prevent the development of cancer.
So how do doctors identify and diagnose whether a person has colon cancer? The colon is accessed via an endoscope from the anus. An endoscope is a ‘camera’ that can probe inside the body, together with the illumination of internal tissue using light shining through a bundle of optic fibres so that doctors can see the walls of the colon or rectum.
When light shines from an external source into the bundle of optic fibres, total internal reflection occurs.This means that 100% of the light is trapped within the fiber and gets transmitted to the end of the fiber, wherever it may be in the colon, thus illuminating the colon. For total internal reflection to occur, light must travel from a higher refractive index to a lower refractive index, and the incident light angle must be greater than the critical angle.
Too abstract to apply it in your daily life? Why not just dive into a pool and look at the surface of the water when you lie under the surface of the water? If the angle is correct, you will see a reflection of your foot due to total internal reflection.
This concept in taught in the physics tuition classes in Miracle Learning Centre. If you are struggling with physics tuition concepts, you will learn and understand them all here.
If you are keen to find out more about total internal reflection, refractive indexes and the applications of physics in daily life, do come down to Miracle Learning Centre to find out more!