Physicaldragging

Physicaldragging is the act of moving an object by applying external contact forces, such as pushing, pulling, or dragging, rather than by self-propulsion. It describes motion produced through interactions at the object's surfaces, including contact with the ground, a fluid, or another body. The outcome is governed by Newton's laws and resisted by friction and drag.

The primary forces are gravity, the normal force, applied forces, friction, and, in fluids, drag. The net force Fnet equals m a. Static friction allows initiation of motion up to Ff,max = μs N, after which kinetic friction μk N applies. In fluids, drag depends on velocity and shape, commonly approximated as Fd = 1/2 ρ Cd A v^2 for turbulent regimes or Fd = η v for viscous regimes. The balance of forces determines whether the object starts moving, accelerates, or maintains constant velocity.

Common forms of physicaldragging include sliding, where an object slides across a surface, and rolling, where it moves with rotation. In liquids or air, viscous and form drag oppose motion and can dominate energy loss. Surface roughness, weight, and contact area affect friction; speed and medium affect drag. The interaction of friction and drag shapes efficiency, energy expenditure, and controllability in practical tasks.

Applications include human locomotion on varied terrains, material handling, and robotics. Safe and efficient dragging requires appropriate gear, alignment to apply force, and awareness of friction and drag coefficients to avoid damage or injury. See also friction, drag, pushing, pulling, dragging (digital).