A piece of wire is redrawn by pulling it until its length is tripled. Compare the new resistance with the original value.

Prove that in series combination of electrical appliances the reciprocal of total power consumption is equal to the sum of the reciprocal of the powers of the individual appliances.

Define resistance of conductor. What is its cause? Explain the factors on which the resistance of a conductor depends.

What do you understand by heating effect of electric current? Explain its cause and find the relation for the heat produced in a conductor by electric current.

Study the following circuit and answer the following questions: (i) State the type of combination of the two resistors in the circuit.

Study the following circuit and answer the following questions:

How much current is following through

$\left(ii\right).\left(b\right) 10 \mathrm{\Omega }$ .

Study the following circuit and answer the following questions:

$\left(ii\right)$How much current is following through $15 \mathrm{\Omega }$  resistors.

Study the following circuit and answer the following questions:

$\left(iii\right)$ What is the ammeter reading.