Advertisements
Advertisements
प्रश्न
Which has less electrical resistance : a thin wire or a thick wire (of the same length and same material)?
Advertisements
उत्तर
A thick wire has a greater area of cross-section, whereas a thin wire has a smaller area of cross-section. Also, the resistance of a conductor is inversely proportional to its area of cross-section. This means that a thick wire has lesser resistance than a thin wire.
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?
What is meant by conductors and insulators? Give two examples of conductors and two of insulators.
Which of the following are conductors and which are insulators?
Sulphur, Silver, Copper, Cotton, Aluminium, Air, Nichrome, Graphite, Paper, porcelain, Mercury, Mica, Bakelite, Polythene, Manganin.
Distinguish between good conductors, resistors and insulators. Name two good conductors, two resistance and two insulators.
What happens to the resistance as the conductor is made thinner?
Which has more resistance:
a thick piece of nichrome wire or a thin piece?
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?
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 length?
What would be the effect on the resistance of a metal wire of:
increasing its temperature?
How does the resistance of a wire change when:
its material is changed to one whose resistivity is three times?
Write the relation between resistance and electrical resistivity of the material of a conductor in the shape of a cylinder of length `'l'` and area of cross-section `'A'` . Hence derive the S.I. unit of electrical resistivity.
Resistance of a metal wire of length 5 m is 100 Ω . If the area of cross - section of the wire is `3 × 10^-7 "m"^2` , Calculate the resistivity of the metal .
Materials which allow larger currents to flow through them are called:
A cylindrical conductor of length l and uniform area of cross-section A has resistance R. Another conductor of length 2l and resistance R of the same material has an area of cross-section:

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 ______.
