User:Sreelekha2003/sandbox

MAKE AN OBJECT INVISIBLE
Making an object invisible is like magical, but this magic is actually indebted to physics

If you have a habit of watching movies like Harry potter, there you can see humans becoming invisible. We may think it is just a magic, but it is actually using a concept of physics. We can construct such an apparatus called as cloaking device which can be employed to hide small objects which are inline with the other objects and it uses a concept called REFRACTION. we can construct the apparatus by using a glass and form an L shaped tank filled with water to get refraction. As cloaking is directly proportional to thickness of tank, cloaking region can be made large. Cloaking device is based on Snell's law. Two L shaped water filled tanks bend light around a cloaking region and bring the light back in the same direction and path. At the first interface, light bends away from the optical axis due to interface with water. The light rays parallel to the optical axis, the second tank brings the light back in the same direction and path. The cloak is based on the idea that light is transversely shifted, but has same direction, after passing through a tilted medium with two straight parallel faces.The set up uses two water filled tanks to bend light around the cloaking region. The first causes all rays below the optical axis to be shifted upwards. After the rays exit the second wall of the displacement relative to their original trajectory. The displacement hides any object in the middle. The second tank undoes the effects of the first tank so that the rays are once again parallel with the effect undone. The width of the cloaking region can be found from Snell's law N1 sin i=N2 sin r.    Using straightforward trigonometry, we find that lateral distance d between the incident ray and the ray after propagating through the medium is given lateral distance d=t sin(i-r)/cos r

Width of cloaking region is given by, Cloaking width = 2xlateral distance. This apparatus hides just small objects but the advanced apparatus using this concept has many applications like hiding objects from satellites which can be useful to any nation's defence system.