Why is a material with high electrical resistivity selected for manufacturing heating elements______________?
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Answer: A. reduce the length of heating element
Explanation
High electrical resistivity allows heating elements to generate required resistance in less space. Shorter wire lengths are easier to install and support within compact industrial furnace designs. This electrical property optimizes heating element geometry while delivering target thermal outputs. Electrical resistance is directly proportional to material resistivity and inversely to area. Heating elements convert electric current into thermal energy via joule heating principles. Materials with high resistivity prevent excessive current draws from standard electrical supplies.
Furnace manufacturers design compact heating coils to fit efficiently inside confined heating chambers. Space saving element designs reduce overall equipment manufacturing and maintenance costs. Industrial resistance heaters rely on high resistivity alloys for reliable thermal performance. Resistivity properties do not directly prevent or reduce chemical oxidation processes. Heating element lifespan depends primarily on alloy purity and operating temperature limits. Large heat production results from power dissipation rather than element length reduction.
- Subject
- Engineering
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- Electrical Engineering
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- —
- Difficulty
- medium
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