Ever wondered why drones use four propellers instead of one? It all comes down to torque, lift, and control. In this video, we break down how opposite-rotating propellers cancel torque, how yaw is achieved by adjusting diagonal pairs, and the real physics behind lift – Bernoulli's principle and Newton's third law. You'll also see why perfect equal speed isn't enough for hovering, and how the onboard computer constantly micro-adjusts for stability. Quick, clear, and packed with engineering insight. Watch and finally understand quadcopter flight!