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How do the resistances of two conducting wires compare if they have the same length, but one is twice the radius of the other?.

Respuesta :

The thicker wire has one-fourth the resistance of the thinner wire.

What are resistance and resistivity?

The characteristic of a substance that prevents the flow of current is known as resistance. The free electrons begin to move in a specific direction when a voltage is applied across the conductor. These electrons collide with atoms or molecules as they move, creating heat in the process. These atoms or molecules prevent free electrons from moving through a substance. Resistance is represented by the symbol R.

Specific resistance is another name for resistivity. A substance with certain dimensions, such as one meter in length and a cross-sectional area of one square meter, has a resistance that is represented by its resistivity. Resistivity or specific resistance is represented by ρ.

The relation between resistance R and resistivity ρ is given as:

                                              R = ρL/A

where,

R = resistance of the conductor

ρ =  resistivity of the material

L = length of the conductor

A = cross-sectional area of the conductor

Calculation:

Given,

r₁ = 2r₂

L₁ = L₂

where

r₁ = radius of the first conductor

r₂ = radius of the second conductor

L₁ = length of the first conductor

L₂ = length of the second conductor

To find

R₁/R₂ =?  (the ratio of R₁ and R₂)

If the radius is twice the other then the area will become,

A₁ = π r₁²

A₂ = π r₂²

A₁ = π (2r₂)²

   = 4π r₂²

Therefore,

A₁ = 4 A₂

Now put the values in the formula,

R = ρL/A

R₁/R₂ = ρ L₁ A₂/  ρ L₂ A₁

R₁/R₂ = L A₂/ L (4A₂)

R₁/R₂ = 1/4

R₁ = R₂/4

Hence, the thicker wire with twice the radius of the thin wire has one-fourth the resistance of the thinner wire.

I understand the question you are looking for is this:

How do the resistances of two conducting wires compare if they have the same length, but one is twice the radius of the other?

(a) The thicker wire has half the resistance of the thinner wire

(b) The resistance is the same in both wires

(c) The thicker wire has one-fourth the resistance of the thinner wire

(d) The thicker wire has twice the resistance of the thinner wire.

Learn more about resistance here:

brainly.com/question/14547003

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