Advertisements
Advertisements
Question
State relative advantages and disadvantages of ring system of wiring over the tree system.
Advertisements
Solution
Advantages:
(i) The tree system of wiring requires the plugs and sockets of different sizes for different current capacities while they are all of the same sizes in the ring system of wiring.
(ii) The tree system of wiring has one fuse in one distribution line. If the fuse in one distribution line blows, it disconnects all the appliances in that distribution line. But in the ring system, a separate fuse is connected with each appliance. So if one fuse blows, it does not affect the other appliances.
(iii) The tree system of wiring is expensive while the ring system of wiring is cheaper.
(iv) It is expensive and inconvenient to install a new appliance in the tree system of wiring since it requires to put the new leads up to the distribution box, while it is easy to install a new appliance in the ring system since the appliance can be directly connected to ring mains in the room.
Disadvantages:
The only disadvantage of the ring system of wiring over the tree system is that while installing a new appliance, care has to be taken that the total load on the ring circuit does not exceed the main fuse rating (i.e., generally 30 amp.).
RELATED QUESTIONS
A 2 kWh heater, a 200 W TV and three 100 W lamps are all switched on from 6 p.m. to 10 p.m. What is the total cost at Rs 5.50 per kWh?
Define 1 kilowatt hour.
Household wiring for lamp connections can either be done in parallel or in series.Which one would you prefer? Give a reason for your answer.
What changes in energy occur in an electric bulb?
An electric filament lamp is connected to a supply of voltage higher than the recommended value. Give reasons, why compared with a normal performance, the lamp emits a brighter light and its life is shortened.
A device is used to transform 12 V a.c. to 200 V a.c. What is the name of this device? Name the principle on which it works.
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate total current taken from the supply.
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate the energy supply in kWh to the three heaters in 5 hour.
I ampere of current is passed through a resistor of resistance R ohm for time t second. Obtain expression for
(i) the electrical energy, and
(ii) the electrical power spent.
An electric bulb is rated as 100W – 250V. What information does it convey? Calculate the current through the filament of the bulb.
