concave lens

a lens that is thinner in the center and thicker at the edges a shape that bends light OUTWARD

convex lens

a lens that is thicker in the center and thinner at the edges a shape that blends light INWARD

reflection

the bouncing back of light waves off of a surface

refraction

the bending of light waves as they travel from one surface to anouther

light

a form of energy that travels in waves and can travel though empty spaces

vibration

to move back and forth rapidly

mass

the amount of matter something has

weight

the measure of the amount of gravity acting on an object's mass

matter

anything that has mass and takes up space

volume

the amount of space taken up by matter

density

the amount of mass an object has in a known volume

mixture

a combination of two or more substances that DO NOT join together to form a new substance

solution

a mixture in which the substances are spread out evenly between one another and cannot be told apart or separated