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Electricity — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceElectricity3 Marks
Question
The electrical resistivities of three materials P, Q and R are given below:

 $\begin{matrix}\text{P}&2.3\times10^{3}\Omega\text{ m}\\\text{Q}&2.63\times10^{-8}\Omega\text{ m}\\\text{R}&1.0\times10^{15}\Omega\text{ m}\end{matrix}$

Which material will you use for making:

  1. Electric wires.
  2. Handle for soldering iron, and
  3. Solar cells?
Give reasons for your choices.

✓

Answer

  1. Material Q with resistivity 2.63 × 10-8 ohm-m can be used for making electric wires because it has very low resistivity.
  2. Material R with resistivity 1.0 × 1015 ohm-m can be used for making handle of soldering iron because it has very high resistivity.
  3. Material P with resistivity 2.3 × 103 ohm-m can be used for making solar cell because it is a semiconductor.

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