how are electron microscope different from light microscope?

Answer 1

First you must have a concept of the wave-particle duality of particles. A regular or optical or "light" microscope works by collecting photons of light that bounce off an object and make an image for you to see in a lense. This is how you see things normally without a microscope--by loight that bounces off objects into your eyes. All the microscope does is allow you to focus in on a smaller area of an object and collect photons originating from a certain point. The lense is what does the focusing.
An electron microscope uses electrons instead of photons to collect information about the object and create an image. The electrons are "focused" by use of a magnetic field. There are now diferent types of electron microscopes: tunneling, scanning, etc. They all do different things with the electrons to gather information and create an image.