## The diagram above is a schematic diagram of a household circuit. The house shown in the above diagram has 5 usable spaces where electrical connections are made. For this house, the mains have a voltage of 220 V and the net current coming from the mains is 22A.

- What is the mode of connection to all the spaces in the house from the mains?
- The spaces 5 and 4 have the same resistance and spaces 3 and 2 have respective resistances of 20Ω and 30Ω. Space 1 has a resistance double that of space 5. What is the net resistance for space 5.
- What is the current in space 3?
- What should be placed between the main connection and the rest of the house’s electrical appliances to save them from accidental high electric current?

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Answer:
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(a) All spaces are connected in parallel.

(b) Let Resistance of Space 5 and 4 be R ohms respectively

Resistance of Space 1 = 2 R ohms

Resistance of Space 2 = 30 ohms

Resistance of Space 3 = 20 ohms

Current = 22 A

V= 220 V

Total Resistance= V/I

(c) Current in space 3, I 3 can be given by:

I3 = V/R

= 220/ 20

= 11A

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(d) Electric Fuses
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can be used to protect circuits (and individual household appliances) from sudden surges in electric current.

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