Factor Affecting Resistance

Ohm’s Law

Resistivity

There are various factors that affect the resistance of the conductor,

Length of the Conductor
Area of Cross-Section of the Conductor
Nature of Material of the Conductor
Temperature

Let’s discuss these effects in detail as follows:

Effect of Length of the Conductor

A conductor’s resistance (R) is proportional to its length (l).

R ∝ l

Effect of Area of Cross-Section of the Conductor

A conductor’s resistance (R) is inversely proportional to its area of cross-section (A).

R ∝ 1/A

Effect of the Nature of Material of the Conductor

A wire’s resistance is determined by the material it is constructed of. While some materials, like copper, facilitate the transmission of electricity, others, like nichrome, do not. The nichrome wire will have roughly 60 times greater resistance than the copper wire if we take two wires of equal length and thickness, but one is made of copper and the other is made of nichrome.

Effect of Temperature

When pure metals are heated, their resistance rises, and when they are cooled, it falls. The reason for this is that when a metal is heated, its atoms move more quickly, which makes it more challenging for electrons to pass through the metal.

The temperature hardly ever has an impact on the resistance of alloys like manganin, constantan, and nichrome. This is a result of the fact that even when heated, the atoms in these alloys find it challenging to move around.

In applications where consistent resistance is necessary, such as in electrical meters and precision instruments, alloys having a low-temperature coefficient of resistance are frequently utilized.

Learn more about Factors Affecting Resistance

Chapter 12 Electricity Notes Class 10 Science

NCERT Notes for Class 10 Physics Chapter 12 Electricity is important to study this chapter carefully because it forms the foundation for many other concepts that you will learn later on. Many exam questions will be based on this chapter, so it is essential to have a good understanding of the material.

Chapter 12 of the NCERT Class 10 Physics textbook explores electricity. It covers a variety of topics, including electric current, circuits, power, resistance in series and parallel, and Ohm’s Law. These notes are designed to provide students with a comprehensive summary of the entire chapter and include all of the essential topics, formulas, and concepts necessary for success on exams.