Question

Find the ratio of resistances of two copper rods X and Y of lengths 30
cm and 10 cm respectively and having radii 2 cm and 1 cm
respectively.​

Answer 1

Explanation:

3:4

Use the formula of resistance in terms of length and area of cross section

Answer 2

Answer:

3:4

Explanation:

Resistance= pL/A

RESISTANCE OF X=ρ*0.3m/ π0.0004m*2   (area=πr*2)

750ρ/π  (3000ρ/4π )

RESISTANCE OF Y=ρ*0.1/π*0.0001m*2

1000ρ/π

RATIO=750ρ/π:1000ρ/π

(on simplifying and stricking the common ρ and π)

3:4

MAKE IT THE BRAINLIEST ANSWER(MY FIRST TIME)