Advertisements
Advertisements
Question
Name three factors on which resistance of a given wire depends and state how is it affected by the factors stated by you.
Solution
The following factors can affect a wire's resistance:
- Length of wire: The resistance increases as the wire length increases. R ∝ (l) (directly proportional).
- Area of cross-section (a): The area of the cross-section has an inverse relationship with resistance. For example, the resistance of a thick wire is lower than that of a thin one.
- Temperature (T): As the temperature rises, the resistance of the wire also rises.
APPEARS IN
RELATED QUESTIONS
Two wires of the same material and same length have radii 1 mm and 2 mm respectively. Compare their resistances.
Assertion (A): Copper is used to make electric wires.
Reason (R): Copper has very low electrical resistance.
Resistance of a wire depends on, ______.
How are the home appliances connected in general, in series or parallel. Give reasons.
The resistance of a conductor is R. If Its length is doubled, then its new resistance will be ______.
Resistors are connected in series if the resistance of the electric circuit is to be ______.
If the area of cross-section of the conductor is doubled its resistance gets ______.
The ______ is the measure of opposition offered by the component to the flow of electric current through it.
Define the following:
Variable resistor
Two copper wires are of the same length, but one is thicker than the other. Which wire will have more specific resistance?