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प्रश्न
State whether the resistance of filament of a bulb will decrease, remain unchanged or increase when it glows.
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उत्तर
The temperature of the filament increases when it glows. So, when the temperature of the wire (bulb filament) increases, ions in it vibrate violently. As a result, the number of collisions increases and hence the resistance increases.
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संबंधित प्रश्न
Write symbol and state function of following component in an electric circuit : key
(a) Complete the circuit given in Fig. by inserting between the terminals A and C. an ammeter.
(b) In the diagram, mark the polarity at the terminals of ammeter and indicate clearly the direction of flow of current in the circuit when the circuit is complete.
(c) Name and state the purpose of Rh in the circuit.

Current in a circuit flows :
A current 0.2 A flows in a wire of resistance 15Ω. Find the potential difference across the ends of the wire.
State the kind of charge on a negative ion.
The following figure shows a metal rod PQ mounted on an insulated stand. The cap of an uncharged electroscope touches one end Q of the metal rod. A negatively charged ebonite rod is brought near the other end P of the metal rod.

(a) What charge does the end P have?
(b) What charge does the end Q have?
(c) What charge does the cap of the electroscope have?
(d) What charge does the gold leaf have?
(e) Will the leaf diverge or collapse? Give reason.
(f) If the electroscope is now earthed, what charge does the metal rod have?
