# Unit 4: Physics

**SCIENCE — WORD WALL**
* Electricity Word List
* Static Electricity — an imbalance of electric charge on the surface of an object
* Electron — a negatively charged particle  in an atom
* Proton — a positively charged particle in the atom’s nucleus
* Electric charge — a form of charge, either positive or negative, that exerts an electric force
* Neutral charge — an object that has equal numbers of protons and electrons
* Negatively charged object — an object that has more electrons than protons
* Positively charged object — an object that has fewer electrons than protons
* Electric force — the force exerted by an object with an electric charge; can be a force of attraction or a force of repulsion
* Induced charge separation — a shift in the position of electrons in a neutral object that occurs when a charged object is brought near it
* Charging by friction — the transfer of electrons between two neutral objects (made from different materials) that occurs when they are rubbed together or come in contact (touch)
* Electrostatic series — a list of materials arranged in order of their tendency to gain electrons
* Charging by conduction — charging an object by contact with a charged object
* Grounding — connecting an object to a large body, like Earth, that is capable of effectively removing an electric charge that the object might have
* Conductor — a material that lets electrons move easily through it
* Insulator — a material that does not easily allow the movement of electrons through it
* Charging by induction — charging a neutral object by bringing another charged object close to, but not touching, the neutral object
* Electric discharge — the rapid transfer of electric charge from one object to another
* Lightning — a bolt of electricity from sky :D
* Current electricity — the controlled flow of electrons through a conductor
* Electric circuit — a continuous path in which electrons can flow
* Switch — a device in an electric circuit that controls the flow of electrons by opening (or closing) the circuit
* Load — the part of an electric circuit that converts electrical energy into other forms of energy
* Electrical energy — the energy provided by the flow of electrons in an electric circuit
* Electric cell — a device that converts chemical energy into electrical energy
* Fuel cell — ?
* Direct current (DC) — a flow of electrons in one direction through an electric circuit
* Alternating current (AC) — a flow of electrons that alternates in direction in an electric circuit
* Electrical power — the rate at which electrical energy is produced or used
* Kilowatt - Hour — the SI unit for measuring electrical energy usage; the use of one kilowatt of power for one hour
* Efficiency — comparison of the energy output of a device with the energy supplied
* Circuit — a way of drawing an electric circuit using standard symbols
* Series circuit — a circuit in which the loads are connected end to end so that there is only one path for the electrons to flow
* Parallel circuit — a circuit in which the loads are connected in branches so that there are two or more paths for electrons to flow
* Potential difference (voltage) — the difference in electrical potential energy per unit charge measured at two different points; measured in volts
* Voltmeter — a device used to measure potential difference (voltage)
* Electrical resistance — the ability of a material to oppose the flow of electric current; measured in ohms
* Ohmmeter — a device used to measure resistance
* Resistor — a device that reduces the flow of electric current
* Ohm’s law — the straight line relationship between voltage and current; R = V/I

