Current Electricity and Electrical InstrumentEasy
Question
A material ′B′ has twice the specific resistance of ′A′. A circular wire made of ′B′ has twice the diameter of a wire made of ′A′. Then for the two wires to have the same resistance, the ratio lA /lB of their respective lengths must be
Options
A.2
B.1
C.
D.
Topic: Current Electricity and Electrical Instrument·Practice all Current Electricity and Electrical Instrument questions
More Current Electricity and Electrical Instrument Questions
If voltage across a bulb rated 220 Volt-100 Watt drops by 2.5% of its rated value, the percentage of the rated value by ...In the circuit shown E, F, G and H are cells of e.m.f 2V, 1V, 3V and 1V respectively and their internal resistances are ...An electric current flows along an insulated strip PQ of a metallic conductor. The current density in the strip varies a...The supply voltage to a room is 120V. The resistance of the lead wires is 6Ω. A 60 W bulb is already switched on. W...A millimeter of range 10mA and resistance is joined in a circuit as shown. The meter gives full-scale deflection for cur...