Question

When does an electric short circuit occur?

Answer 1

Hint: In an electrical circuit, it is crucial to maintain the proper flow of current in the correct and desired direction. Any disturbance in the circuit resulting in the wrong flow of charge will affect the circuit, making it futile.

Complete step-by-step answer:
A short circuit is defined as an abnormal connection between two nodes of an electrical circuit from which current travels along an unintended path with very low electrical impedance. This allows excessive current flowing through the circuit which can cause circuit damage, overheating, fire, explosion, and even severe damage to electrical appliances.
A normal short circuit occurs when a live wire carrying current and a neutral wire comes in contact due to damaged insulation or faulty appliance which causes resistance to go down instantly and a severe surge in the current flowing through the circuit.
Some major causes of electrical short circuits are-
1. Faulty or Old Circuit Wire Insulation
2. Faulty Appliance Wiring
3. Loose Wire Connections
4. Overloading a circuit for very long durations

Additional Information:
i. Short Circuit can be identified by monitoring connections and appliances for burns, smoke, damage, sparks, or buzzing sounds.
ii. Short circuits can also occur due to lightning strikes, which is why it is recommended to use less electricity during heavy storms.
iii. Using fuses and circuit breakers or MCBs can prevent a short circuit by interrupting abnormal current flow.

Note: Short Circuits can be dangerous as they can release large amounts of heat energy due to high voltages of power sources causing damage to life and material. Fire due to short circuits happens because of overcurrent which causes ohmic heating of the parts of the circuit with improper insulation or poor conductivity.