Q. 265.0( 2 Votes )
In a household electric circuit, different appliances are connected in parallel to one another. Give two reasons
An electrician puts a fuse of rating 5A in that part of domestic electrical circuit in which an electrical heater of rating 1.5 kW, 220V is operating. What is likely to happen in this case and why? What change, if any, needs to be made?
The two reasons for connecting the appliances in parallel are as follows.
1. Each appliance will be at same potential (voltage).
2. If one of the appliances fails the other will still keep working.
Voltage = 220V;
Power = 1.5kW = 1500W
(1kW = 1000W)
P = VI
The current in the circuit is 6.8A
Since the current in the circuit is more than the rating of the fuse (5A)the fuse will blow off.
A fuse of rating 10 A should be put off in the circuit
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