Specific resistance?

Question

What's the importance of specific resistance of a electric conductor?Give answer with example.

Answer 1

The specific resistance, otherwise known as the resistivity, is the material (but not shape) dependent information you need to know when calculating the resistance of a piece of something. For Cylindrically-shaped resistors, the resistance is

(resistivity)*(length)/(cross sectional area)

This makes sense--doubling the cross sectional area should halve the resistance because it's like having twin resistors in parallel, while doubling the length should double it because it's like having twin resistors in series.

Answer 2

The amount of resisstance in a electrical circuit determins the amount of current flowing in the circuit.

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Formula for current

I = V/R

I = current
V = voltage
R = Residtance or ohms

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Example;

I =100/25

I = 4amp

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Increasing the resistance

I = 100/50

I = 2 amps

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In the example we increased the residtance from 25 to 50 ohms, the results was a decrease in current. Resistance is inversely proportional to current

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Specific residtance depends on the density of the material.Different materials have different density. There the more the resistant the material decreased the flow of current. Providing the voltage is constant.

Answer 3

The resistance of a particular object (may it be conductor or insulator) depends on its specific resistance and its physical dimensions. It is a property of the material irrespective of its shape and size. So knowing the specific resistance one can design the dimensions of the object to get a particular value of resistance for that object.

Answer 4

Specific resistance of a conductor is the density of the material, The more dense the metal the better the conductivity. Gold is a dense metal and a very good conductor. Aluminum is not as dense, it has more O molecules making it a poorer conductor. Cooper has a resistivity of 10.4 ohms per ft. whereas aluminum is 17.1 ohms per ft. so copper is better than aluminum.

Answer 5

Higher the specific resistance, greater the resistance.

Answer 6

specific resiatance is the inherent property of the material of the conductor and decides how good or bad a conductor is