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a piece of wire of resustance R is cut into five equal parts. These parts are then connected in parallel. if the equivalent resistance of this combination is R', then what is the ratio R/R'? |
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Answer» of wire of resistance R is cut into five equal parts. These parts are then connected in parallel . if the equivalent resistance of this combination is R' , then what is the RATIO R / R' ?The equivalent resistance of 5 RESISTANCES ( R₁ , R₂ , R₃ , R₄ , R₅ ) connected in parallel will be given by LET , initial length of wire = 5 L initial area of cross section = A then,initial Resistance = R will beNow,∵ Wire is DIVIDED in 5 equal parts Therefore,new length of each wire PIECE = L area of cross section of each wire piece = A( area of cross section will remain unchanged)so,new resistance of each part will be5 pieces were connected in parallel connection so, Equivalent resistance of parallel combination = R' will be ▶ Now finding the ratio R / R'Hence ,the ratio R : R' = 25 : 1 |
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