Examples of external forces include the force applied to the system, air resistance of an object, force of friction, tension and normal force. Internal forces include the force of gravity, spring force, and magnetic and ... More »

The equation for net external force is the sum of all the external forces applied to the object. For example, a compilation of common external forces is friction force, normal force, air resistance, tension and applied f... More »

An external force is a force that originates from an object outside of a defined system. For example, if a system is defined as only the bob in a pendulum, both the rope and gravity exert an external force on the bob. If... More »

Wind resistance, a type of friction also known as drag, is the relative opposing force imparted on an object as it moves against still air. The wind resistance on an object depends on the square of its velocity, so as th... More »

The force that slows down the movements of an object through a liquid or gas is known as drag, or air resistance. In some cases, this force is also referred to as friction, but classically, friction occurs in solid objec... More »

The upward force acting upon a falling object is called air resistance, according to Georgia State University. Often referred to as drag in aerodynamics, air resistance works in the opposite direction from which an objec... More »

Examples of fluid friction include hailstones falling from the atmosphere, the drag of air on an airplane, water slowing the speed of a boat, air slowing a bullet and fish swimming underwater. Fluid friction occurs aroun... More »

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