Advertisements
Advertisements
Question
Advertisements
Solution
Factors on which the resistance of a conductor depends are:
(i) Nature of conductor: different materials have different concentration of free electrons and therefore resistance of a conductor depends on its material.
(ii) Length of conductor: Resistance of a conductor is directly proportional to the length of a conductor.
(iii) Area of cross-section of a conductor: Resistance of a conductor is inversely proportional to the area of cross-section of the uniform wire.
(iv) Temperature of conductor: In general for metallic conductors, higher the temperature larger is the resistance.
Materials which allow electric charges to flow through them easily are known as conductors. E.g. metals and materials which do not allow the electric charge to flow through them are known as insulators. E.g. rubber, dry wood etc.
APPEARS IN
RELATED QUESTIONS
Calculate the number of electrons constituting one coulomb of charge.
Draw the electrical symbols of the following components and state its use
Wire crossing
One coulomb charge is equivalent to the charge contained in:
(a) 2.6 × 1019 electrons
(b) 6.2 × 1019 electrons
(c) 2.65 × 1018 electrons
(d) 6.25 × 1018 electrons
What is international convention of colour coding in a cable?
Find the effective resistance in the following circuit diagrams (Fig.):
In a house there are 6 bulbs of 100 W each used for 4 hours a day, 4 bulbs of 60 W each used for 8 hours a day, an immersion heater of 2.5 kW used for 1 hour per day, and an electric iron of 800 W used for 2 hours per day. Calculate the cost of monthly electric bill for the month of April at the rate of 80 p per unit.
A bulb is connected to a battery of p.d. 4 V and internal resistance 2.5 Ω . A steady current of 0.5 A flows through the circuit. Calculate:
The total energy supplied by the battery in 10 minutes
Which part of an electrical appliance is earthed?
Conventionally, the direction of the current is taken as:
