A uniform plank is balanced on a sharp pivot at its center. Which condition specifically ensures the plank does not rotate when weights are added?
Q1. A uniform plank is balanced on a sharp pivot at its center. Which condition specifically ensures the plank does not rotate when weights are added?
Answer: Στ = 0
Explanation: Second condition of equilibrium (Στ = 0) prevents rotation. Option A only ensures the object does not move linearly.