Advertisements
Advertisements
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?
Concept: undefined >> undefined
Why are copper and aluminium wires usually employed for electricity transmission?
Concept: undefined >> undefined
Advertisements
Write the molecular formula of the 2nd and 3rd member of the homologous series whose first member is ethene.
Concept: undefined >> undefined
List the factors on which the resistance of a conductor in the shape of a wire depends.
Concept: undefined >> undefined
Why are alloys commonly used in electrical heating devices? Give reason.
Concept: undefined >> undefined
Fill in the following blanks with suitable words:
Copper is a good .......... Plastic is an ..........
Concept: undefined >> undefined
What is meant by conductors and insulators? Give two examples of conductors and two of insulators.
Concept: undefined >> undefined
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.
Concept: undefined >> undefined
What is the general name of the substances having infinitely high electrical resistance?
Concept: undefined >> undefined
Which has less electrical resistance : a thin wire or a thick wire (of the same length and same material)?
Concept: undefined >> undefined
Distinguish between good conductors, resistors and insulators. Name two good conductors, two resistance and two insulators.
Concept: undefined >> undefined
Classify the following into good conductors, resistors and insulators:
Rubber, Mercury, Nichrome, Polythene, Aluminium, Wood, Manganin, Bakelite, Iron, Paper, Thermocol, Metal coin
Concept: undefined >> undefined
What is meant by the "resistance of a conductor" ? Write the relation between resistance, potential difference and current.
Concept: undefined >> undefined
What happens to the resistance as the conductor is made thinner?
Concept: undefined >> undefined
Name the electrical property of a material whose symbol is "omega".
Concept: undefined >> undefined
What happens to the resistance as the conductor is made thicker?
Concept: undefined >> undefined
Which among iron and mercury is a better conductor of electricity?
Concept: undefined >> undefined
Which has more resistance:
a long piece of nichrome wire or a short one?
Concept: undefined >> undefined
Which has more resistance:
a thick piece of nichrome wire or a thin piece?
Concept: undefined >> undefined
What do you understand by the "resistivity" of a substance?
Concept: undefined >> undefined
