A large number of household appliances use magnets. Electromagnets are magnets that can be activated and deactivated through the application of electricity. This is useful in a number of common household items. People use them in their everyday lives, such as the magnets installed into shower curtains in order to easily stick them to the wall. A similar function is used in refrigerators.
Your refrigerator uses a magnetic strip in its door. All refrigerators must seal to lock out the warm air and keep cool air inside. A magnet is what allows these seals to be so effective. The magnetic strip runs the length and width of the refrigerator and freezer door.
A solenoid is an electromagnetic coil. This is a piece of metal with a wire around it. When electricity is applied to the wire, the metal becomes magnetic. Many dishwashers have a timer activated magnetic solenoid underneath them. When the time is up, according to Repair Clinic.com, the solenoid opens a drain valve that drains the dishwasher.
Televisions and Computers
All cathode ray tube, or CRT, televisions have magnets inside them. According to the How Magnets Work website, the image on any CRT TV is produced as a stream of electrons from an electron ray gun in the back of your TV. This stream is directed down a tube, called the cathode ray tube. The electrons travel straight until they are affected by electromagnets, along the sides of the tube. The electromagnets direct the stream toward the corners, sides and middle of your TV screen, allowing you to see it as it appears.
Computers use magnets in several ways. First, CRT computer screens are produced like television screens. The electromagnets bend the stream of electrons making it visible on a large screen. According to How Magnets Work, computer disks are coated with metal that stores and transmits electromagnetic signals in patterns. This is how the information is stored on a computer disk.
LCD and plasma screens for both televisions and computers have static liquid crystals or gas chambers and do not operate the same way. These new technologies are not affected by magnets in household objects the way that a CRT screen would be.
You can tell how many magnets a doorbell contains simply by listening to the number of tones it produces. According to the Knox News website, doorbells also contain solenoids like dishwashers. The solenoid in a doorbell causes a spring-loaded piston to strike a bell. It happens twice, because as you release the button the magnet passes beneath the piston again causing it to strike. This is where the "ding dong" sound comes from. Doorbells that have more than one tone have more than one chime, piston and magnet.