Question

PTO-driven rotavator with rotor radius 30 cm, speed = 4.5 km/h, working at 12 cm depth. Find the torsional moment on the blade.

Hint:

Use torque = force × radius for rotational motion.

Answer 1

Correct Answer: 8.9

Blade width = 12 cm = 0.12 m. Rotor radius = 30 cm = 0.30 m. Working depth = 12 cm = 0.12 m. Tangential force: \[ F = 150\ \text{N} \] Torsional moment: \[ M = F \times r = 150 \times 0.30 = 45\ \text{N·m} \] Thus, \[ \boxed{45.0\ \text{N·m}} \]