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if the fuse wire in a house is constructed so that the maximum current flowing through it is 5 amper. If the potential differences used is 110volts how many lamps can be lightened at the same time in such house knowing that the resistance of the other parts of the circuit equal 2 om

there's a missing given .
power of each lamp is 25 watts. from which u can determine resistance of each lamp using the 5 amperes current so .. from (V/I)-r u can find total resistance ((110/5)-2 = 20 ohm)2 .
now u have R=20 ohm , use equation of power to find R of each lamp
25=I**2)R)
therefore R of each = 1 ohm
20 = NR

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