define the term resistance of a material in terms of its specific resistance . how can you vary the specific resistance of a wire
Answers
Explanation ⇒ Resistance is defined as the obstruction offered to the flow of electrons.
If you want to define it in terms of Specific Resistance, then let us see its mathematical expression.
Now, R = ml/ne²τA
Where m is mass, l is length of conductor, n is free electrons density, A is area of conductor and τ is avg. relaxation time.
m,n,e,τ are constant. Thus, m/ne²τ is named as constant = ρ = Resistivity or specific resistance.
∴ R = ρl/A
When A = 1 m² and l = 1 m, then,
R = ρ
''In terms of Physics, Resistance is defined as the resistivity of the conductor when electrons flows in an conductor of length 1 m and unit area. ''
Hope it helps.
➡️Specific resistance of a conductor is the resistance of a conductor of unit length and unit area of cross section.
➡️Specific resistance is a property of a material while resistance is not.
➡️Resistance increases with length and decreases with area of cross section, but specific resistance does not.