On what factors does resistance of a conductor depend? Describe an experiment to study the factor on which the resistance of a conducting wire depends.
Answers
Answer :-
Resistance :- The property of a material to resist the flow of electric current through itself is called resistance.
Resistance of a conductors depends upon the following factors :-
- Length of the conductor.
As the length increases the resistance of conductor will also increases.
- Cross section area of the conductor.
When area of cross section is increased the resistance of the conductor decreases.
- Temperature of the conductor.
Resistance increases with increase in temperature of the conductor.
- Nature of the material.
Resistance also depends upon the nature of the material of the conductor.
From this we concluded the formula of resistance given by :-
Experiment to show that the resistance of a conductor depends on above mentioned factors.
Aim :-
To show that the resistance of a conductor depends on its length and area of cross section.
Material required :-
Wire of different length and different cross section area, battery,
key , voltmeter, ammeter etc.
Procedure:-
First make a closed circuit by connecting battery and key.
Now take a point A and B and insert different lengths of wire and carefully measure the reading of voltmeter and ammeter.
By using the ohms law R = V/I
Make an observation table for the following observations Now, connect the wire of different area of cross sections.
Observation :-
You will find that more the length of wire more its resistance.
And, more the area of cross section less its resistance.
Conclusions :-
- Length is directly proportional to resistance of wire.
- Area is inversely proportional to resistance of wire.
Answer:
The resistance of a conductor depends directly on its length, inversely on it's area of cross section, and also on the material of the condutor.