Science Chapter 12

current in which charged particles travel through a circuit in only one direction

• A current in which electrons move back and forth in a circuit
• -ised for moving large amount of electricity
• -electron net movement is 0

• Electrical device that changes the size of potential difference of an alternating current
• -only for AC

A safety device that is placed in series with other circuits that lead to appliances and outlets

A safety device that is found in older buildings and some appliances; like a circuit breaker, it is placed in the series with other circuits that lead to appliances and outlets

The rate at which an appliance uses electrical energy

• Unit of electrical power;
• 1 kW = 1000 W

• A practical unit of electrical power;
• 1 kW = 1000 W

The energy that is used by an appliance at a given setting; is determined by multiplying its power rating by the length of time it is used

The practical unit of electrical energy

A label that gives details about how much energy an appliance uses in one year of normal use

a meters that records the total electrical energy used hour by hour and sends this information to the utility company automatically

A system of pricing in which the cost of each kWxh of energy used is different at different times of the day

-electricity is less expensive at night usually because there is less demand 

The electricity that is consumed by an appliance or device when it is turned off

e.g. light on a TV that is off

The ratio of useful energy output to total energy output, expressed as a percentage

nuclear power plants are 94.9% efficiency (they lose 5.1% of energy in the process)

The continuous minimum demand for electrical power

-met with hydroelectric and nuclear power

The production of electricity using a source of moving water

A demand for electricity that is greater than the base load

-met by burning coal and natural gas

The greatest demand for electricity

-met by using hydroelectric power and natural gas

A source of energy that can be replaced in a relatively brief period of time

e.g. wind, hydro, geothermal

A source of energy that cannot be replaced as quickly as it is used

e.g. coal, nuclear, biomass

Energy that is directly converted from the energy of the sun into electricity

-converted using solar panels

The generation of a direct current when certain materials are exposed to light

-used in solar panels

Energy that is generated from plant and animal matter