Advertisements
Advertisements
Question
Classify the following into good conductors, resistors and insulators:
Rubber, Mercury, Nichrome, Polythene, Aluminium, Wood, Manganin, Bakelite, Iron, Paper, Thermocol, Metal coin
Advertisements
Solution
Conductors: mercury, aluminium, iron and metal coin
Resistors: nichrome and manganin
Insulators: rubber, polythene, wood, paper, thermocol and bakelite
APPEARS IN
RELATED QUESTIONS
On what factors does the resistance of a conductor depend?
What is the general name of the substances having infinitely high electrical resistance?
What is meant by the "resistance of a conductor" ? Write the relation between resistance, potential difference and current.
Name the electrical property of a material whose symbol is "omega".
What happens to the resistance as the conductor is made thicker?
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?
Give two examples of substances which are good conductors of electricity. Why do you think they are good conductors of electricity?
How does the resistance of a conductor depend on:
length of the conductor?
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?
Calculate the area of cross-section of a wire if its length is 1.0 m, its resistance is 23 Ω and the resistivity of the material of the wire is 1.84 × 10−6 Ω m.
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.
The element used almost exclusively for filaments of incandescent lamps:
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:
Assertion: Conductors allow the current to flow through themselves.
Reason: They have free charge carriers.
How will the resistance of a wire be affected if its
- length is doubled, and
- radius is also doubled ?
Give justification for your answer.
