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A piece of wire of resistance R is cut into five equal parts. These parts are then connected in parallel. If the equivalent resistance of these of this combination is R then the ratio RR is

Answer
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Hint: The question talks about the connection of resistors together to fix the end (parallel connection) with a certain length of wire cut in bits into five portions of basically the same length, cross sectional area and resistivity. When the resistors are connected in parallel, then the reciprocal of the equivalent resistance is the sum of the reciprocals of all the resistances.

Complete step by step answer:
We are given that a piece of wire of resistance R is cut into five equal parts and these parts are then connected in parallel. The equivalent resistance of these of this combination is R
Since the resistors are equal in values then, we might decide to name the first resistor as R1, the second resistor as R2, the third resistor as R3, the fourth resistor as R4 and the fifth resistor as R5.
So for resistors in parallel, the equivalent resistor becomes 1R=1R1+1R2+1R3+1R4+1R5
Also since the resistor (R) is divided into R1=R2=R3=R4=R5
R=R1+R2+R3+R4+R55R1=RR1=R5R1=R2=R3=R4=R5=R5
We can then simplify
 1R=1(R5)+1(R5)+1(R5)+1(R5)+1(R5)1R=5R+5R+5R+5R+5R1R=25RRR=251
Therefore, the ratio RR is 251, R:R=25:1

Note:
Same applies to inductors connected in parallel too but differs in a capacitor. The voltage of resistors connected in series is different for each resistor and current is the same for all the resistors in series, whereas the voltage of resistors connected in parallel is the same for each resistor and current is different for all the resistors. The same resistance of a wire is dependent on three factors or parameters namely resistivity, cross sectional area and length.
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