Heating Effect of Electric Current is Used in Various Appliances like
- Electric Bulb
- Electric Iron
-
Electric Fuse
Let's study them one by one
Electric Bulb
Electric bulb contains following
- Thin Filament made of Tungsten metal
- Connecting Copper Wire to make current pass
- Glass Covering
- Argon or Nitrogen Gas enclosed in the bulb
When electric current is passed through tungsten filament
it glows and produces light and heat
Note-
Tungsten Metal is used to make filament because
It offers higher resistance ,and produces more heat
it has very high melting point (3380 Degree Celsius) .It does not melt while producing heat
Note-
Argon or nitrogen Gas is used instead of Oxygen in Glass Bulb because
they do not react with tungsten like oxygen
This makes the bulb last longer
Electric Iron and Electric Kettle
These contain
- Coils(Circular wires) made of Nichrome Metal
- Connecting Copper Wires
Note = Nichrome is an alloy of nickel and chromium
It offers high resistance and produce large amount of heat
They are connected to copper wires which are good conductor of electricity but offer very little resistance and hence very less heat
Hence, When electric current is passed
Copper wire doesn't heat up,it only passes electricity to Nichrome Coil
But Nichrome Coils get heated up producing large amount of heat
This heat is used for ironing clothes or heating water.
Electrical Fuse
What is an Electrical Fuse?
Fuse is an electrical safety device
If excess current flows through an appliance,it breaks off the circuit
Thus it prevents overheating of appliance and electrical fires
How does Fuse work?
It contains wire made of metal like aluminium,copper,lead etc
these metals have low melting point
When excess current flows through circuit,the metal wire melts. Thus, breaking the circuit
Thus it prevents overheating of electrical appliance and electrical fires.
