Physics, asked by Rizvi1, 1 year ago

The specific resistance of a wire is p, its volume is 3m^3, and its resistance is 3ohm. then what eill be its length?

Answers

Answered by shivam8899

resistance of wire = ρl/A

l = length of wire
A = area of wire

l x A = volume
so we can also write

R = ρl^2 / lA = ρl^2 / V

3 = ρl^2 /3
so l^2 = 9/ρ
so l = 3 / √ρ meter

i hope it will help you

regards

Rizvi1: options. a) √ (1/p) b) 3/p c) √3 / p d) p √(1/3)

shivam8899: 3 / √ρ is answer..bt tumhare otions se shi clarify nhi ho pa rha

Rizvi1: tell me in english.. i dont knw hindi

shivam8899: 3 / √ρ is answer...but by ur options don't clarify real otion ..may be u din't write..right option

shivam8899: d is correct option

shivam8899: if in question has 3 √ (1/p) like of option that will be correct option

Answered by JunaidMirza

R = pL/A
To answer this question you should know above fromula.

Rearrange above equation to find L
L = RA / p
L = R × V/L × 1/p ……[∵ Area = Volume / Length]
L² = RV / p

L = √[(RV) / p]
= √[(3 Ω × 3 m³) / p]
= 3 / √p

Length of wire is 9 / √p

Rizvi1: options.. a) √(1/p) b) 3/p c) √3/ p d) p× √(1/p)

JunaidMirza: No option is correct.

JunaidMirza: Btw neglect the last line of my answer. I mistakenly wrote 9/√p instead of 3/√p

Previous Question

Next Question