Question

please tell me the answer​

Answer 1

Answer will be 21 % Explanation is attached

Hope it helps you

Answer 2

Answer:

Resistance of a wire

R = ρL/A

Find out how much the cross-sectional area changes.

Volume of a cylinder = cross-sectional area * h

V = Ah

Initial volume V₁ = A₁h₁

Final volume V₂ = A₂h₂

∴ Volume does not change .

Length of wire is increased by 10%.

A₁h₁ = A₂h₂

=> A₁/A₂ = h₂/h₁ = 1.1

So cross-sectional area will go down by 1.1

Now resistance calculation ,

Initial resistance R₁ = ρL₁/A₁

Final resistance R₂ = ρL₂/A₂

R₂/R₁ = (ρL₂/A₂) * (A₁/ρL₁)

R₂/R₁ = (L₂/L₁) * (A₁/A₂)

So the ratio is the product of the two

R₂/R₁ = 1.1 * 1.1

R₂/R₁ = 1.21

Therefore, resistance goes up by 21%.

Hope it helps!