8.1: Electric potential energy and voltage

Battery

Combination of electrochemical cells connected together(or a single electrochemical cell). Purpose of battery is to give electrons stored electrical energy.

Electrochemical cells

Convert chemical energy into electrical energy stored in charges. Commonly referred to as cells or batteries. In a battery, chemical energy separates the positive and the negative charges.

Voltmeter

Device that measures potential difference between two locations of charge separation. One needle placed at + terminal, one needle placed at - terminal of the battery and the voltmeter displays the battery's voltage.

Electric potential energy

Electrical potential energy is the electrical energy stored in a battery, because electrons have a stored energy and the ability to do work after they leave the battery.

Kinetic energy

Energy, a moving object because of its motion. Related to heat and kinetic molecular theory.

Piezoelectric crystals

Ex: Barbecue lighter. Electricity comes from a tiny crystal when squeezed, positive and negative charges are separated on either sides of the crystal. Generates a thousand volts of electricity when a small hammer in the lighter hits the crystal.

Thermocouples

A device used to transform heat energy into electrical energy. Consists of a loop of two wires of different metals joined at both ends.

Electrolyte

A substance that conducts electricity in a battery. Electrolyte is a moist paste in dry cells, but a liquid in wet cells.

Energy

Ability to do work, ability to move.

Wet cells

Batteries commonly used in cars, automobiles, motorcycles, electric wheelchairs. Both produce voltage in the same way.

Dry cells

Batteries in devices like flashlights, portable CD players, watches. One of the two groups in batteries.

Voltage

Potential difference, or voltage. The amount of electrical potential difference per one coulomb of charge.

Friction

Rubbing two materials together to produce charge. One of the sources of producing electrical energy. Can result in one object losing electrons and one gaining electrons.

Photo-electrochemical cells

Solar panels/ calculators use this as a source of power. Made of semi-conducting materials such as silicon. When light hits the cell, some of the light energy breaks electrons off the surface of the cell. Separated electrons now have energy to operate something.

Potential difference(voltage)

The amount of electrical potential energy per one coulomb of charge.

Terminals

The points where we make a connection at the battery. One end is positively charged and one end is negatively charged. Extra electrons accumulate on one end of the battery terminals, therefore it is negatively charged. Meanwhile, the other terminal has lost electrons and become positively charged. In a circuit, electrons are pushed from the negative terminal of the battery, along the conducting wires, and ends up at the positive terminal of the battery.

Electrodes

Two terminals of the battery which are usually made up of two different metals. Located in an electrolyte. Electrodes have an opposite charge, there is potential difference between the two electrodes.

Volt(V)

Unit for measuring potential difference.( or voltage). Amount of voltage produced in an electrochemical cell depends on type of metal and electrolyte used.

Generators

When a wire moves closet to a magnet, a voltage is created across the wire. All needed is an energy source to provide the wire or the magnet with necessary motion. In BC, we use hydroelectric energy(water energy) to provide electricity.