Question

(A) Write any two precautions to be taken to avoid electrical accidents. (B) State how these precautions prevent possible damage to the electric circuit.

Accepted Answer

1. Earthing of metal bodies. 2. Use of electrical fuses/MCBs of proper rating. Earthing prevents shock; fuse breaks circuit during overloading.. (A) **Precautions:** 1. **Earthing of electrical appliances:** Connect metallic bodies of appliances to the earth wire. 2. **Use of electric fuse / MCB:** Install fuses/MCBs of correct current rating in the circuit. (B) **How they prevent damage:** - **Earthing:** Provides a low-resistance path for leakage current to ground, keeping the potential of the metal body equal to ground, preventing fatal electric shocks. - **Electric Fuse:** Melts due to Joule heating ($H = I^2Rt$) when current exceeds safe limits during overloading or short circuiting, breaking the circuit and protecting appliances.

Electrical Safety Precautions

Explanation

Practise this under board exam conditions