What is the electrical resistance of an object?

Electrical Resistance can be defined as the resistance towards the current when it moves via a bulb or any conductor. Electrical resistance is represented by the alphabet R. The unit of resistance is Ohm (Ω).

Step 1: Ohm’s Law

According to Ohm's law,

V ∝ I

$\therefore$ V = IR

Here,

V = Potential Difference (in Volts).
I = Current (in Amperes)
R = Resistance (in Ohms).

Step 2: Factors That Affect Electrical Resistance

Electrical resistance is proportional to a conductor's length and is also inversely proportional to its cross-sectional area.

$R = \rho {{L} \over A}$

Where,

L = Length.
A = Cross-sectional Area
ρ = Resistivity in Ohm meter (Ωm).

Some factors that affect electrical resistance include:

The cross-sectional area, length, and material of the given conductor.
The conducting material's temperature.

Hence, an object’s electrical resistance is directly proportional to the length and is also inversely proportional to the cross-sectional area.

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What is the electrical resistance of an object?

Step 1: Ohm’s Law

Step 2: Factors That Affect Electrical Resistance

CBSE CLASS XII Related Questions

2.
With the help of a labelled diagram, explain the principle, construction and working of an a.c. generator.

4.
This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

Similar Physics Concepts

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What is the electrical resistance of an object?

Step 1: Ohm’s Law

Step 2: Factors That Affect Electrical Resistance

CBSE CLASS XII Related Questions

2.With the help of a labelled diagram, explain the principle, construction and working of an a.c. generator.

4.This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?

Similar Physics Concepts

Comments

SUBSCRIBE TO OUR NEWS LETTER

2.
With the help of a labelled diagram, explain the principle, construction and working of an a.c. generator.

4.
This ‘average velocity’ is found be few mm/s for currents in range of a few amperes. How then is current established almost the instant a circuit is closed ?