Energy Transfers in Appliances Flashcards
All 5 cards in this deck
In an electric motor (e.g. in a washing machine), what is the main energy transfer?
Electrical energy is transferred to the kinetic energy store of the moving parts (some is wasted as thermal energy and sound).
In a heating device such as a kettle, what is the main energy transfer?
Electrical energy is transferred to the thermal energy store of the water (and surroundings).
True or false? For the same time of use, a 2000 W kettle transfers twice as much energy as a 1000 W heater.
True. Energy transferred , so double the power means double the energy in the same time.
What supplies the electrical energy in a battery-powered device compared with a mains appliance?
A battery supplies a d.c. p.d. from its chemical energy store; mains appliances use a.c. mains.
What does the power rating of an appliance tell you?
The most energy it can transfer every second while it is running, i.e. its maximum operating power in watts.