Question Statement:
Which of the following statements regarding flat and troughed belt conveyors for bulk grain handling are CORRECT?
Options:
- (A) Troughing the belt using 3-roll idlers (at $20^\circ\text{ to }45^\circ$ troughing angles) increases cross-sectional capacity by up to two to three times compared to a flat belt of identical width
- (B) The maximum permissible belt incline angle is strictly limited by the grain dynamic angle of friction on the belt surface (typically $15^\circ\text{ to }18^\circ$ for cereal grains)
- (C) Belt drive power transmission depends on the angle of wrap $\theta$ and friction coefficient $\mu$ between belt and drive pulley according to Euler's formula $T_1 / T_2 \le e^{\mu \theta}$
- (D) Belt conveyors cannot operate at speeds exceeding $0.5\text{ m/s}$ due to inevitable seed germination damage