Science vocab chapter 12

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

E.g. anything that uses a battery

• A current in which electrons move
• back and forth in a circuit

• E.g. anything that is powered by
• an electrical grid

• An electrical device that changes
• the size of the potential difference of an alternating current

• E.g. an object may only need 110V, and a
• transformer will change 1,000V into that

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

• E.g. usually put in place in case of lightning
• strikes, so that appliances don’t short circuit

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

E.g. old houses electrical panels have fuses

• The rate at which an appliance
• uses electrical energy

E.g. a dryer takes greater electrical power than a toaster

• A unit of electrical power; 1
• kilowatt = 1,000W

E.g. a dryer uses 4,510 watts

• A practical unit of electrical
• power; 1kW = 1,000W

E.g. a dryer uses 4.51kW

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

• E.g. even though a dryer uses more power, a water heater is
• running for longer, making use more energy

The practical unit of electrical energy

• E.g. the amount of kW∙h of a appliance that uses 5 kW over 2 hours is
• 10kW∙h

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

E.g. the rating of a dryer is 912 kW∙h

• A meter that records the total electrical energy used hour
• by hour and sends this information to the utility company automatically

E.g. found commonly on the side of houses

• A system of pricing in which the cost of each kW∙h
• of energy used is different at different times of the day

• E.g. earlier in the day costs less than in the
• afternoon

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

E.g. toasters, cellphones, tv’s

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

E.g. incandescent light bulbs are 5% efficient

The continuous minimum demand for electrical power

E.g. Ontario’s is 12, 000MW

• The generation of electrical power using a source of moving
• water

E.g. using a dam as hydroelectric power generation

• A demand for electricity that is greater than the base load
• and is met by burning coal and natural gas

E.g. Ontario’s is 15, 000MW to 20, 000MW

• The greatest demand for electricity, which is met by using hydroelectric
• power and natural gas

E.g. Ontario’s is above 20, 000MW

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

E.g. solar power, wind energy, hydropower

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

E.g. fossil fuels

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

E.g. solar panels

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

E.g. solar panels

Energy that is generated from plant and animal matter

E.g. burning plants