aluminum: A metallic element, the third most abundant in Earth’s crust. It is light and soft, and used in many items from bicycles to spacecraft.
average: (in science) A term for the arithmetic mean, which is the sum of a group of numbers that is then divided by the size of the group.
axis: (in mathematics) The line to the side or bottom of a graph. It is labeled to explain the graph’s meaning and the units of measurement.
clay: Fine-grained particles of soil that stick together and can be molded when wet. When fired under intense heat, clay can become hard and brittle. That’s why it’s used to fashion pottery and bricks.
computer program: A set of instructions that a computer uses to perform some analysis or computation. The writing of these instructions is known as computer programming.
copper: A metallic chemical element in the same family as silver and gold. Because it is a good conductor of electricity, it is widely used in electronic devices.
data: Facts and/or statistics collected together for analysis but not necessarily organized in a way that gives them meaning. For digital information (the type stored by computers), those data typically are numbers stored in a binary code, portrayed as strings of zeros and ones.
diameter: The length of a straight line that runs through the center of a circle or spherical object, starting at the edge on one side and ending at the edge on the far side.
electric charge: The physical property responsible for electric force; it can be negative or positive.
electricity: A flow of charge, usually from the movement of negatively charged particles, called electrons.
electromagnetism: The science that has to do with the physical links between electricity and magnetism. It’s also the term for the properties of an electric current that cause it to generate a magnetic field. This term can also be applied to the physical force (the electromagnetic force) that governs interactions between charged particles and which are due to their electric charge and their release or absorption of light (photons).
electron: A negatively charged particle, usually found orbiting the outer regions of an atom; also, the carrier of electricity within solids.
fabric: Any flexible material that is woven, knitted or can be fused into a sheet by heat.
glass: A hard, brittle substance made from silica, a mineral found in sand. Glass usually is transparent and fairly inert (chemically nonreactive). Aquatic organisms called diatoms build their shells of it.
horizontal: A line or plane that runs left to right, much as the horizon appears to do when gazing into the distance.
humidity: A measure of the amount of water vapor in the atmosphere. (Air with a lot of water vapor in it is known as humid.)
lightning: A flash of light triggered by the discharge of electricity that occurs between clouds or between a cloud and something on Earth’s surface. The electrical current can cause a flash heating of the air, which can create a sharp crack of thunder.
magnetism: The attractive influence, or force, created by certain materials, called magnets, or by the movement of electric charges.
metal: Something that conducts electricity well, tends to be shiny (reflective) and is malleable (meaning it can be reshaped with heat and not too much force or pressure).
nylon: A silky material that is made from long, manufactured molecules called polymers. These are long chains of atoms linked together.
plastic: Any of a series of materials that are easily deformable; or synthetic materials that have been made from polymers (long strings of some building-block molecule) that tend to be lightweight, inexpensive and resistant to degradation. (adj.) A material that is able to adapt by changing shape or possibly even changing its function.
polyester: A synthetic material used chiefly to make fabrics. The actual chemical name for the material used is polyethylene terephthalate.
shock: (in biology and medicine) A potentially fatal bodily reaction to a variety of conditions, including illness, injury, blood loss and lack of adequate water, usually characterized by marked loss of blood pressure, decreased blood circulation and inadequate blood flow to the tissues.
silk: A fine, strong, soft fiber spun by a range of animals, such as silkworms and many other caterpillars, weaver ants, caddis flies and spiders.
square: (in geometry) A rectangle with four sides of equal length.
static: The condition of being unmoving and unchanging. (in physics) An electronic signal that contains no information but does contain random fluctuations in intensity or wavelength.
static electricity: The buildup of excess electric charge on some surface instead of flowing through a material. This charge buildup tends to develop when two things that are not good conductors of electricity rub together. This allows electrons from one of the objects to be picked up and collected by the other.
Styrofoam: A trademarked name for a type of rigid foam made from light-weight polystyrene plastic. It is used for everything from home craft projects to decorative ornaments and building insulation.
triboelectric: An adjective to describe an electric charge that develops when two things rub against each other, causing friction.
vertical: A term for the direction of a line or plane that runs up and down, as the vertical post for a streetlight does. It’s the opposite of horizontal, which would run parallel to the ground.
wood: A porous and fibrous structural tissue found in the stems and roots of trees, shrubs and other woody plants.
x-axis: (in mathematics) The horizontal line at the bottom of a graph, which can be labeled to give information about what the graph represents.
y-axis: (in mathematics) The vertical line to the left or right of a graph, which can be labeled to give information about what the graph represents.