Observing that the bulb does not glow in the circuit shown in Fig. 14.11 A, Boojho changed the circuit as shown in Fig 14.11 B. He observed deflection in the magnetic compass.

(i) What does the deflection in magnetic compass indicate?
(ii) Why did the bulb not glow in Fig.14.11 A?
(iii) What would be the effect of increase in the number of turns in the coil wound around the magnetic compass in Fig. 14.11B?
(iv) What will be observed if the number of cells are increased in the circuit shown in Fig. 14.11B?

Explanation

(i) It indicates the presence of current in the circuit.
(ii) The bulb did not glow because the current was not sufficient to make it glow.
(iii) Deflection in the magnetic compass will increase.
(iv) Deflection in the compass will increase further.