Concave Mirror Diameter 5cm, Focal Length 5cm / 7.5cm / 10cm / 20cm / 30cm

A concave mirror is a mirror that is curved inward in the middle. It might help you to remember this if you think that when you look in a concave mirror, it looks like you are looking into a cave. The equation we use when dealing with concave mirrors is called the mirror equation. This equation is used to determine how far away an object is from the mirror (image distance) and how large or small the object is (object size.)