The total count of particles in a crushed sample is expressed as (where m = sample mass, Vp = volume of a single particle, and ρ = particle density) ?
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Answer: A. m/ρ . Vp
Explanation
The total count of particles in a sample is calculated by dividing total mass by individual particle mass. Mass equals the product of single particle volume and particle density, giving the correct formula. This mathematical relation allows estimation of total particle population in crushed material samples. Particle statistics and count estimations are important in powder technology and surface area calculations. Assuming uniform particle geometry simplifies the calculation of individual particle volume. Density links mass measurements directly to volumetric particle dimensions in granular samples.
Researchers use particle count formulas to analyze specific surface areas in fine powder samples. Pharmaceutical powder quality control requires understanding particle population distributions. Accurate particle counting helps evaluate the effectiveness of industrial comminution circuits. Multiplying mass by density and dividing by volume inverts the dimensional units incorrectly. Placing volume in the numerator with mass creates an invalid dimensional ratio for particle counting. Reversing density terms leads to incorrect physical units incompatible with particle number derivation.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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