short circuit simply means, when a positive and the negative electric charge collided or met in a certain point.
If there is an electric short, the resistance of the circuit would be zero. So you can use an ohm meter to test it.
The fuse is there to disconnect the supply when there is a short circuit, before any damage is done.
Electric circuit need a main circuit breaker that can protect the whole circuit from short circuit even in ground fault. It's safer if you use breaker with built in ground protection.
A: As current approaches infinity on a device it is known as a current source.
When the electrical appliances are not connected well or the cables of the electric appliances are worn out,a short circuit may occured. A short circuit affects the normal operation of electrical appliances connected to the circuit.It has very low resistance that almost all electric current would flow through it.Owing to the heating effect,an excess electric current would produce heat and thus may damage the electric appliances,or even cause a fire,if without a fuse or a circuit breaker.
A Short Circuit
a short
A fuse places a limit on the amount of current that can be drawn by an electric circuit by opening (blowing or melting) when the current exceeds a preset limit. This protects the circuit and the surroundings from fire or damage in the case of an overload or short circuit.
When the cables of the electrical appliances are worn out or it's not connected properly,a short circuit may occure.A short circuit has a very low resistance that almost all electric current flow through it.It'll affect the operation of the electrical appliances.Owing to the heating effect,the excess electric current would produce a large amount of heat,wihout a fuse or a circuit breaker,a fire may be occured when there's a short circuit.
Consider two points (A and B) in an electric circuit. An open circuit between A and B means there is no electrical connection between A and B. A short circuit between A and B means there is an electrical connection between A and B.
You will get a short circuit if two uninsulated parts of the supply conductors, touch each other. You can also get a short circuit if the "hot" supply conductor touches any grounded metallic part of the system.
To prevent an overload or short from causing the wiring in the circuit supplying power to the appliance from overheating and possibly catching on fire. The fuse is there to protect the wiring and not what is plugged into that circuit.