Advertisements
Advertisements
प्रश्न
What happens to the resistance as the conductor is made thinner?
Advertisements
उत्तर
The resistance of a wire can be represented by the following equation:
`R=(rhol)/A`
So, when the conductor is made thinner, its area of cross-section will decrease, since resistance is inversely proportional to the area of the conductor. Therefore, its resistance will increase.
APPEARS IN
संबंधित प्रश्न
Two conducting wires of the same material and of equal lengths and equal diameters are first connected in series and then parallel in a circuit across the same potential difference. The ratio of heat produced in series and parallel combinations would be:
A copper wire has diameter 0.5 mm and resistivity of 1.6 × 10−8Ω m. What will be the length of this wire to make its resistance 10 Ω? How much does the resistance change if the diameter is doubled?
Why are copper and aluminium wires usually employed for electricity transmission?
What is meant by conductors and insulators? Give two examples of conductors and two of insulators.
Which has less electrical resistance : a thin wire or a thick wire (of the same length and same material)?
Name the electrical property of a material whose symbol is "omega".
A wire is 1.0 m long, 0.2 mm in diameter and has a resistance of 10 Ω. Calculate the resistivity of its material?
What will be the resistance of a metal wire of length 2 metres and area of cross-section 1.55 × 10−6 m2 if the resistivity of the metal be 2.8 × 10−8 Ω m?
Calculate the resistance of a copper wire 1.0 km long and 0.50 mm diameter if the resistivity of copper is 1.7 × 10−8 Ω m.
How does the resistance of a conductor depend on:
temperature of the conductor?
What would be the effect on the resistance of a metal wire of:
increasing its diameter?
What would be the effect on the resistance of a metal wire of:
increasing its temperature?
Materials which allow larger currents to flow through them are called:
The element used almost exclusively for filaments of incandescent lamps:
Plastic insulation surrounds a wire having diameter d and length l as shown above. A decrease in the resistance of the wire would be produced by an increase in the ______.
The resistance of a wire of 0.01 cm radius is 10 Ω. If the resistivity of the wire is 50 × 10-8 Ω, find the length of this wire.
How will the resistance of a wire be affected if its
- length is doubled, and
- radius is also doubled ?
Give justification for your answer.
