Fig. 12.10 A and B, show a bulb connected to a cell in two different ways.

(i) What will be the direction of the current through the bulb in both the cases. (Q to P or P to Q)
(ii) Will the bulb glow in both the cases?
(iii)Does the brightness of the glowing bulb depend on the direction of current through it?

A bulb is connected to a cell and the potential differ-ence across the terminals of the bulb is 24 V. If 3 A of current flows through the bulb, then the resitance of its filament is "_____"omega .

A wire connected to a bulb does not glow, whereas the filament of the bulb gilows when same current flows through them. Why?

A student connected the terminals P and Q by a piece of thread. Will the bulb glow?

Three incandecent bulbs of 100 W each are connected in series in an electric circuit. In another circuit another set of three bulbs of the same wattage are connected in parallel to the same source. (a) Will the bulbs in the two circuits glow with the same brightness ? Justify your answer. (b) Now let one bulb in both the circuits get fused. Will the rest of the bulbs continue to glow in each circuit ? Give reason.

Three incandescent bulbs of 100 W each are connected in series in an electric circuit. In another circuit, another set of three bulbs of the same wattage are connected in parallel to the same source. (a) Will the bulbs in the two circuits glow with the same brightness ? Justify your answer. (b) Now let one bulb in both circuits get fused. Will the rest of the bulbs continue to glow in each circuit ? Give reason. (a) In a household electric circuits, different appliances are connected in parallel to one another. Give two reasons for the same. (b) An electrican puts a fuse of rating 5 A in that part of domestic electrical circuit in which electrical heater of rating 1.5 kW, 220 V is operating. What iis likely to happen in this case and why ? What change, if any, needs to be made ?

Surbhi sets up the apparatus as shown to test the electrical conductivity of vinegar. She finds that the current passing through the circuit is not strong enough to make the bulb glow. What other device could she use in place of the bulb so that it glows even under weak current

Paheli connected two bulbs to a cell as shown in Fig. 12.8. She found that filament of bulb B is broken. Will the bulb A glow in this circuit? Give reason.