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Read the given passage and answer the following questions: The home electrical connection consists of ‘live’, ‘neutral’ and ‘earth’ wires. The ‘live’ and the ‘neutral’ wires - Science and Technology 1

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Question

Read the given passage and answer the following questions:

The home electrical connection consists of ‘live’, ‘neutral’ and ‘earth’ wires. The ‘live’ and the ‘neutral’ wires have potential difference of 220 V. The ‘earth’ is connected to ground. Due to a fault in the equipment or if the plastic coating on the ‘live’ and the ‘neutral’ wires gives a way the two wires come in contact with each other and a large current flows through it producing heat. If any inflammable material (such as wood, cloth, plastic, etc.) exists around that place it can catch fire. Therefore a fuse wire is used as a precautionary measure.

  1. Name the two wires having potential difference of 220 V.
  2. What is a short circuit?
  3. Write the function of a fuse.
Answer in Brief

Solution

  1. The ‘live’ and the ‘neutral’ wires have potential difference of 220 V.
  2. Due to a fault in the equipment or if the plastic coating on the ‘live’ and the ‘neutral’ wires gives away the two wires come in contact with each other and a large current flows through it producing heat. This is known as short circuiting.
  3. Fuse wire protects circuits and appliances by stopping the flow of any excess electric current.
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2019-2020 (March) Set 1

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