What is the difference between direct current and alternating current?,|How do electric fuses work?Why don t birds sitting on a high-voltage wire get a shock?

Why don t birds sitting on a high-voltage wire get a shock?

Electricity travels from a place of high voltage to low voltage,just like water travels naturally form high elevation to low elevation.If the bird sits on a wire and also touches the ground,a path is created that allows electricity to travel through the body and to the place with no voltage.When electricity travels though the body of the bird in this fashion,electrocution takes place,and the bird dies.However,if the bird touches a single wire it does not get a shock because electric current passes through the wire instead of the bird.

What is the difference between direct current and alternating current?

In direct current,electrons flow only in one direction,but in alternating current,electrons keep switching their directions.Due to significant advantages of alternating current over direct current,electrical power distribution is nearly all in the form of alternating current today.For many appliances,such as lamps,direction of flow of electrons does not matter;for others,such as computers,the flow needs to be uniform.Hence a rectifier is connected to a computer,which converts the alternating current into direct current.

How do electric fuses work?

Fuses break the electric circuit when the current becomes very strong owing to any overload.As a result,the wires are never too hot,and a fire is prevented.In safety fuses,such as those used in cars or in screw-locking devices in homes,a thin wire inside the fuse melts when it gets heated by a very strong electric current.The fuse blows and must be replaced.In modern fuses,the circuit is broken with the help of an electromagnet,which 'jumps out'to break the circuit.When the fault has been fixed it is easily reset by pressing the switch.