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Electricity — Science STD 10 — Question

CBSE BoardEnglish MediumSTD 10ScienceElectricity4 Marks
Question
The table shows four different materials and their resistivity.
MaterialResistivity(Ω m)
Material 11.62 ×10-8
Material 2100 ×10-6
Material 36.84 ×10-8
Material 444 ×10-6
1. Which material is the best conductor of electricity?
A. Material 1
B. Material 2
C. Material 3
D. Material 4
2. What is the SI unit of Resistivity?
3. Why is nichrome wire used in many electrical heating devices?
A. It has low resistivity and low melting point.
B. It has high resistivity and low melting point.
C. It has low resistivity and high melting point.
D. It has high resistivity and high melting point.
✓

Answer

1. A. Material 1
2. Mentions ohm-meter (Ω m) as correct response. 
3. D. It has high resistivity and high melting point. 

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