Identify the incorrect assertion among the choices ?
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Answer: A. The concentric layer in atmosphere which contains about 70% of the total mass of atmosphere
Explanation
Alloying silicon into steel disrupts the periodic atomic lattice, increasing electrical resistance. Higher electrical resistance is a desirable trait because it minimizes eddy current power losses. Therefore, claiming silicon decreases electrical resistance contradicts established metallurgical principles. Electrical steels used in transformers contain specific percentages of silicon to improve magnetic efficiency. Alloys are generally harder than pure metals because foreign atoms obstruct dislocation glide movements. Karbate is an impervious graphite material widely used for handling corrosive acids in chemical plants.
Transformer cores are built from silicon steels to reduce energy waste and heat generation during operation. Electrical equipment designers rely on high-resistance core materials to maximize energy transmission efficiency. Identifying incorrect assertions is a crucial skill in materials science quality control evaluations. Alloys being harder than component elements is a correct statement due to solid solution strengthening. Karbate being an acid-resistant construction material is entirely true and well documented in industry. Nichrome retaining useful strength up to eleven hundred degrees Celsius is a correct engineering fact.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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