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