Aerodynamic force of bird problem

[harp AP 2010]

Homework Statement

A bird is caught in an updraft and ascends at a steady rate. Which has greater magnitude: gravity or aerodynamic force?

Homework Equations

The Attempt at a Solution

Is it the aerodynamic force because the bird is moving up, against gravity?

 

[physx_420]

That sounds right to me.

 

[donutz610]

Yes because it must be greater to counteract the force gravity exerts on the bird. It is the aerodynamic force.

 

[physx_420]

Yes because it must be greater to counteract the force gravity exerts on the bird. It is the aerodynamic force.

Word.

 

[rwisz]

I would approach this problem by first defining the terms "aerodynamic force" and "gravity." Aerodynamic force is the force exerted on an object by air as it moves through the air, while gravity is the force of attraction between two objects with mass. In this case, the bird is experiencing both aerodynamic force and gravity as it is caught in an updraft and ascending.

To determine which force has a greater magnitude, we can look at the equations that describe these forces. The aerodynamic force on an object is typically described by the equation F = ½ρv²ACd, where ρ is the density of air, v is the velocity of the object, A is the frontal area, and Cd is the drag coefficient. On the other hand, the force of gravity is described by the equation F = mg, where m is the mass of the object and g is the acceleration due to gravity.

Since the bird is ascending at a steady rate, we can assume that its velocity is constant. Therefore, the aerodynamic force is proportional to the density of air, frontal area, and drag coefficient. On the other hand, the force of gravity is proportional to the mass of the bird. Without knowing the specific values for these variables, it is impossible to determine which force has a greater magnitude without further information.

However, we can make some assumptions based on the situation. If the bird is able to maintain a steady ascent in an updraft, it is likely that the aerodynamic force is greater than the force of gravity. This is because the bird is able to overcome the force of gravity and continue ascending, indicating that the aerodynamic force is strong enough to counteract the force of gravity.

In conclusion, the magnitude of the aerodynamic force and gravity on the bird will depend on various factors such as air density, frontal area, drag coefficient, and mass. Without more information, it is impossible to determine which force has a greater magnitude. However, based on the bird's ability to maintain a steady ascent in an updraft, it is likely that the aerodynamic force is greater than the force of gravity in this situation.