Math, asked by PrathamSaini4672, 1 month ago

A 4 ampere wire is doubled on it. Calculate the new resistance of the wire.

Answers

Answered by Disha094
20

We consider wire is doubled on it means to fold the length of wire. It means its length will get half and area of cross section will get doubled. Thus, R' = p' l'/A' = p (l /2) ÷ 2A = !/4 (p l / A) = 1/4R = 1/4× 4 = 1Ω.

Answered by sunprince0000
0

Answer:We consider wire is doubled on it means to fold the length of wire. It means its length will get half and area of cross section will get doubled.

∴ Let the resistance of the wire originally 'R' of length 'L' and area of cross-section 'A' with resistivity of material is 'p',

Then

R = p l/A = 4Ω

Now, for new arrangement,

p' = p

l' = l / 2

A' = 2A

Thus,  

R' = p' l'/A' = p (l /2) ÷ 2A = !/4 (p l / A) = 1/4R = 1/4 × 4 = 1Ω.

            or another method

When the wire is doubled the length will be halved and area will be double or twice  

R = PL/A  

R1 = P(L/2) / 2A Where R1 is the new resistance  

So R1/R = {P(L/2) / 2A} / {PL/A}  

When we solve this we get  R1/R = ¼  

=> R1 = R/4 = 4/4 = 1 OHM

Step-by-step explanation:

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