Solve this A wire .0 m long. 0.2 nim in diameter, has a resi IWo metallic wires A and (of the same material) are connected in parallel. Wire A has length and radius r; wire B has a length 31 and radius 3r. Compute the ratio of the total resistance of parallel combination and the resistance Of wire A. It-three resistors having resistances 20.3Q and 50 are connected in parallel. then will the value or-the total resistance be less than 20 , or greater than 2 Q or lie-between 20 and 5 Q Explain. A piece or wire having resistance is cut into four equal parts. (i) How will the resistance Of each part compare with the original resistance? (ii) Ifthe four parts are placed in parallel. how wilt the resistance of the c€»nbination cotnparc with the resistance Of the original wire? piece of wire of resistance R is redrawn by pulling it until its length is doubled. Compare lew resistance with the original value. •wo lamps; one rate 100 W at 220V. and the other 60W at 220V. are connected in parallel to a 20V supply. What is the current drawn from the supply line? the circuit diagrant given in fig. calculate: ) (he current through each resistor ) to total current in the circuit ) the total effective resistance of the circuit. Why a bird perched on a high voltage wire is not killed by current? How many 176 Qresistors (in parallel) are required to carry a current of 5 A in 220V line? Narne an instruntent that measures electric current in a circuit. Define the unit 01' electric ent. What do the following synbols mean in a circuit diagram? in electric circuit consisting ofa 0.5 m long nichrome wire X Y. an ammeter. a volttneter, cells ot- 1.5 V each and plug key set up. t is the advantage of the third "ire of earth connection in d01nestic appliances? 'hat ractors does the lörce experienced by a current — carrying conductor placed in a unif 'etic field depend? can the strength of an electromagnet be increased? is the difference between an electromagnet and permanent magnet? hat is meant by the term •magnetic field'? hy does a compass needle show deflection when brought near a magnet? are magnetic field lines? How is the direction of magnetic field at a point d on two important properties of magnetic field lines. is series arrangement not used for domestic circuits? of copper wire is connected to a galvanometer. What would happen if a is: t into the coil with north pole entering first (ii) pulled out ofthe coil (iii) held stauOnan