$A$ nichrome wire has a resistance of $10\, \Omega$. Find the resistance of another nichrome wire,whose length is three times and area of cross-section four times the first wire.

The potential difference across a conductor is doubled,the rate of generation of heat will

$A$ wire of resistance $10 \, \Omega$ is bent in the form of a closed circle. What is the effective resistance between the two points at the ends of any diameter of this circle?

Elements of electric toasters and electric irons are made of an alloy rather than a pure metal. Give two reasons to justify the statement.

$(a)$ $A$ Nichrome wire of length $L$ and radius $r$ has a resistance of $10 \, \Omega$. How would the resistance of the wire change when:
$(i)$ only the length of the wire is doubled?
$(ii)$ only the diameter of the wire is doubled? Justify your answer.
$(b)$ Why are the elements of electrical heating devices made up of alloys?

Potential and potential difference are vector quantities.