Which of the following types of bucket elevator is most commonly... | Agrigyan

Heat removed is given by $Q = m \cdot c \cdot \Delta T$. Here $Q = 500\text{ kcal}$, mass $m = 5\text{ tons} = 5000\text{ kg}$, and specific heat $c = 0.1\text{ kcal/(kg}\cdot^\circ\text{C)}$. Solving for temperature drop: $\Delta T = \frac{Q}{m \cdot c} = \frac{500}{5000 \times 0.1} = \frac{500}{500} = 1^\circ\text{C}$. Option analysis: (A) $5^\circ\text{C}$ is incorrect. (B) $0.1^\circ\text{C}$ is incorrect. (C) $1^\circ\text{C}$ is the exact calculated temperature drop. (D) $10^\circ\text{C}$ is incorrect.

Assertion (A) is true: excessive feeding overloads the rotating plates, causing power surges, motor stalling, and unevenly coarse ground product. Reason (R) is true: grinding fineness in burr/attrition mills is governed by the plate surface corrugations and the axial clearance gap between plates. However, (R) does not explain why overfeeding degrades performance (overfeeding degrades performance due to inadequate energy transfer and plate separation). Hence (R) is NOT the correct explanation of (A). Option analysis: (A) (R) does not explain the overfeeding mechanism. (B) Both (A) and (R) are true but (R) is NOT the correct explanation of (A). (C) (R) is true. (D) (A) is true.

Freeze drying (lyophilization) freezes the moisture in food into ice and sublimates it directly from solid ice to water vapor under deep vacuum ($\lt 4.58\text{ mmHg}$, below the triple point of water), preserving cellular structure, aroma, and rehydration properties. Option analysis: (A) Drum drying works by conductive evaporation. (B) Spray drying works by hot air convective droplet evaporation. (C) Thin layer drying operates on convective hot air evaporation. (D) Freeze drying works strictly by sublimation.