The electrical resistivity of few materials is given below in ohm-metre. Which of these materials can be used for making element of a heating device ?
$A$ | $6.84 \times 10^{-8}\, \Omega m$ |
$B$ | $1.60 \times 10^{-8}\, \Omega m$ |
$C$ | $1.00 \times 10^{-4}\, \Omega m$ |
$D$ | $2.50 \times 10^{12}\, \Omega m$ |
$E$ | $4.40 \times 10^{-5}\, \Omega m$ |
$F$ | $2.30 \times 10^{17}\, \Omega m$ |
A material having high value of resistivity is used for making element of heating devices, therefore, material $C$ will be used. Material $F$ cannot be used as it is an insulator.
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