A wave bounces back from a wall that it cannot destroy or be propagated through. This bouncing back is called reflection and is shown in the picture above. We are usually interested in reflection of electromagnetic radiation. For example, light is reflected by a mirror. A mirror is something that cannot absorb or propagate light… Continue reading 22.4 Reflection

Before you read this, I suggest you read post 22.1. The magnifying glass is a bi-convex lens that uses the light from an object to trick the eye into thinking the object is bigger than it really is. The way is works can be explained by ray-tracing, as shown in the picture below. In the… Continue reading 22.3 The magnifying glass

Before you red this, I suggest you read post 22.1. A projector is a device that uses light emitted by an original image to produce a larger version of that image on a screen (the projected image), as shown in the picture above. In this picture the blue arrow points upwards but in the projected… Continue reading 22.2 The projector

Before you read this, I suggest you read post 19.21. The picture shows an object (in yellow) with two convex curved surfaces. This object is made of a material whose refractive index in air, n, is greater than 1; we will suppose that this material is glass but it could be any transparent material with… Continue reading 22.1 Refraction at curved surfaces – lenses