Physics Of Bird Flight

Explaining Flight

1.1: The Physics of Bird Flight: Components:

I. Drag: (Air Resistance) The force opposite to the force of the motion of an object through a fluid. (Fluid in this report refers to the medium the bird/object is moving through- i.e. Air). Drag is created because the object and the fluid are exchanging momentum upon impact, and thus creating a force opposite to the motion of the object. Equation for drag: Fd = 1/2(Cd * A * ρ * v2)

FD: Drag Force

Cd: Drag Constant

A: Area ρ: Density of Fluid v: Flow Velocity relative to Object

Instrument to measure Drag: Force Balance

Speed: Similar to surface it is also included in the equation and is directly proportional to Drag force. Fluid Density: Increased density means an increase

(Short wide wings) Maneuverability: The low aspect ratio combined with different flight maneuvers allows the bird for more agility and easier movement.

V. Work and Heat:

The work done during bird flight can be calculated as follows: Work= Force x Distance x sinƟ

Due to the Law of Conservation of Energy, heat is accumulated through bird flight. Having an average body temperature of 40°C, the birds will not simply store this extra heat. Instead, this amount of heat will be dissipated out of the wings. This is possible because of the existence of several air sacs. Air sacs are a system of thin fibrous containers which temporarily store hot air. These air sacs are found throughout the bird in its neck, thorax, and wings. Therefore, the extra heat is conducted out of the air sacs located at the bird’s wings.

Also, at low temperatures, birds and other animals having air sacs can warm up their bodies during periods of low

Bird Strategies: As stated in the previous point, the animals have certain maneuvers that help them in their journeys. Some of the likes as decreasing their surface area to decrease drag across the opposing flow of the fluid. They achieve this by closing their wings, which will increase their speed. They also try to increase lift by rapidly flapping its wings to push it upwards. As stated later, they also use their large flight muscles to produce thrust that allows them easier passage. Another very important strategy that large winged animals use is the soaring one. Their large bodies make it hard for them to stay lifted therefore, they would use the only efficient possibility available and start to float across the fluid. Without this fundamental strategy, the bird would continuously flap its wings and burn lots of