A technician often has to sketch or design ductwork and the other parts of an HVAC system. Sometimes you have to sketch the room or building you are working with. This means working with lines, angles ...

An angle is created when two lines meet. There are different types of angles based on their measurement. Let's look at the different types. A right angle looks like the corner of a square or the edge ...

Refraction close refractionProcess by which a wave changes speed and sometimes direction upon entering a denser or less dense medium, eg a light ray changes direction when refracted by a lens. of ...