Two electric bulbs A and B are rated 60 W and 100 W, respectively. If they are connected in parallel to the same source, then,

(1) both the bulbs draw the same current

(2) bulb A draws more current than bulb B

(3) bulb B draws more current than bulb A

(4) currents drawn in the bulbs are in the ratio of their resistances

Figure 7.44 shows three similar lamps $L_1, L_2 and L_3$ connected across a power supply. If the lamp $L_3$ fuses, how will the light emitted by $L_1 and L_2$ change?

(1) no change

(2) brilliance of both $L_1$ decreases and that of $L_2$ increases

(3) brilliance of both $L_1 and L_2$ increases

(4) brilliance of both $L_1 and L_2$ decreases

A factory is served by a 220 V supply line. In a circuit protected  by a fuse marked 10 A, the maximum number of 100 W lamps in parallel that can be turned on is :

1. 11 

2. 22

3. 33

4. 66

A 100 W bulb designed to operate on 100 V is to be connected across a 500 V source. Find the resistance to be put in series so that bulb consumes 100 W only.

(1) 100 $\Omega$

(2) 500 $\Omega$

(3) 400 $\Omega$

(4) 300 $\Omega$

A torch bulb rated \(4.5\) W, \(1.5\) V is connected as shown in the figure below. The emf of the cell needed to make the bulb glow at full intensity is:

The reading of an ideal voltmeter in the circuit shown is:

The metre bridge shown is in a balanced position with \(\frac{P}{Q} = \frac{l_1}{l_2}\). If we now interchange the position of the galvanometer and the cell, will the bridge work? If yes, what will be the balanced condition?

The resistance of hot tungsten filament is about 10 times the cold resistance. What will be the resistance of 100 W and 200 V lamp when not in use?

(1) 14,000 $\Omega$

(2) 400 $\Omega$

(3) 40 $\Omega$

(4) 4 $\Omega$

Three bulbs of 40 W, 60 W, and 100 W are connected in series with a 240 V source. Then,

(1) The potential difference will be the maximum across the 40 W bulb.

(2) The current will be the maximum in 100 W bulb.

(3) The resistance of the 40 W bulb is the minimum.

(4) The current through the 60 W bulb will be 0.1 A.

A wire, when connected to a \(220~\text{V}\) mains supply, has power dissipation \(P_1.\) Now, the wire is cut into two equal pieces, which are connected in parallel to the same supply. Power dissipation in this case is \(P_2.\) Then \(P_2:P_1\)  is :
(1) 1

(2) 4

(3) 2

(4) 3