Advertisements
Advertisements
प्रश्न
Which has more resistance:
a long piece of nichrome wire or a short one?
Advertisements
उत्तर
A long piece of nichrome wire has more resistance because the resistance of a conductor is directly proportional to its length, R α l.
APPEARS IN
संबंधित प्रश्न
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?
Fill in the following blanks with suitable words:
Copper is a good .......... Plastic is an ..........
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.
What is the general name of the substances having infinitely high electrical resistance?
Which has less electrical resistance : a thin wire or a thick wire (of the same length and same material)?
What is meant by the "resistance of a conductor" ? Write the relation between resistance, potential difference and current.
What happens to the resistance as the conductor is made thinner?
What happens to the resistance as the conductor is made thicker?
Give two examples of substances which are good conductors of electricity. Why do you think they are good conductors of electricity?
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:
area of cross-section 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 diameter?
How will you infer with the help of an experiment that the same current flows through every part of the circuit containing three resistors R1, R2 and R3 in series connected to a battery of V volts?
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 ______.
How will the resistance of a wire be affected if its
- length is doubled, and
- radius is also doubled ?
Give justification for your answer.
