Devices convert electrical energy into many useful forms , such as heat -LRB- electric heaters -RRB- , light -LRB- light bulbs -RRB- , motion -LRB- electric motors -RRB- , sound -LRB- loudspeaker -RRB- or chemical changes .

Devices convert this work into many useful forms , such as heat -LRB- electric heaters -RRB- , light -LRB- light bulbs -RRB- , motion -LRB- electric motors -RRB- and sound -LRB- loudspeaker -RRB- .
