Page 5 - X-CBW-ELECTRICITY

= 0 to 0.5 A at t = t₁. The voltage of the power supply is 200 V and remains
constant throughout.
(A) Based on the graph, state how the resistance of the bulb filament
changes as the temperature increases from time t = 0 to t = t1.

(B) What is the power consumed by the bulb when it is glowing at its full
brightness?
15 The picture shown below is of a special bulb P which is used in some circuits 3
of series lights. Its filament is joined to the two terminals through a
bimetallic strip, as shown. When the filament gets heated and glows, it also
heats up the bimetallic strip which bends when heated.

Besides its function as a light bulb, which other component of a normal
electric circuit is this bulb likely to function as? Justify your answer.
16 The picture below shows two diagrams of the wiring of an electric clothes 3
iron. The thermostat is a device that can be set at a particular temperature,
and controls the heating temperature of the iron by automatically shutting
off and on. The indicator light is connected differently in the two diagrams.

(a) Explain how the difference in the connections affects the functioning of
the indicator light.
(b) Does this difference change the heating of the iron? Justify your answer.
(c) State the function of the earthing wire.