Advertisements
Advertisements
Question
The diagram shows two ways of connecting three lamps P, Q and R to A.C. supply of 220 V.


Advertisements
Solution
The arrangement is shown in the figure (i) is a series arrangement. The arrangement in figure (ii) is the parallel arrangement.
We prefer a parallel arrangement. The reasons are:
(i) In series arrangement, if one of the bulbs is fused, the other bulbs also cease to glow. But in a parallel arrangement, if one bulb fuses, the other bulbs continue to glow.
(ii) In the series arrangement, while one bulb glows if the other bulb is switched on, the resistance of the circuit increases, and hence the bulbs glow less bright. But in a parallel arrangement, each bulb glows at the same voltage, therefore the glow of a bulb is unaffected if another bulb is switched on.
APPEARS IN
RELATED QUESTIONS
1 A = _________ mA
- 102
- 103
- 10-3
- 10-6
What is the Flow of Charge Called?
In 10 s, charge of 25 C leaves a battery, and 200 J of energy are delivered to an outside circuit a result.
What is the p.d. across the battery?
(a) With the help of a circuit diagram, obtain the relation for the equivalent resistance of two resistances connected in parallel.
(b) In the circuit diagram shown below, find:
(i) Total resistance.
(ii) Current shown by the ammeter A

Ten bulbs are connected in a series circuit to a power supply line. Ten identical bulbs are connected in a parallel circuit to an identical power supply line.
(d) Which circuit would have less current in it?
Define the following:
Super conductors
A wire is passed through a piece of cardboard as shown in fig .. An electric current flows vertically down the wire and then flows back up. The two sections of the write are observed to repel each other.
(a) Wi th the aid of a diagram, describe how you would plot the magnetic field lines on the card .

(b) Sketch the magnetic field patterns around both the sections of the wire. Use your sketch to explain why the two sections repel each other.
(c) The repulsive force between the two sections is small. What changes could be made to increase it?
Complete the following:
1 kWh = _________ J
