Current Electricity and Electrical InstrumentHard
Question
Three copper wires of lengths and cross sectional areasare (l,A), (2l,A/2) and(l/ 2,2A). Resistance is minimum in
Options
A.wire of cross -sectional area A/2
B.wire of cross - sectional area A
C.wire of cross - sectional area 2A
D.same in all the three case
Solution
R ∝ 
;
So, the resistance of the wire will be minimum when the area of cross-section is maximum and length is minimum
;So, the resistance of the wire will be minimum when the area of cross-section is maximum and length is minimum
Create a free account to view solution
View Solution FreeTopic: Current Electricity and Electrical Instrument·Practice all Current Electricity and Electrical Instrument questions
More Current Electricity and Electrical Instrument Questions
For the resistance network shown in the figure, choose the correct option(s)...The contribution in the total current flowing through a semiconductor due to electrons and holes are and respectively. I...A copper wire stretched so as to make it 0.1% longer. The percentage increase in the resistance of the wire is : -...The conductivity of a super conductor is : -...In the given potentiometer circuit, the resistance of the potentiometer wire AB is R0. C is a cell of internal resistanc...