Directly Downwind Faster Than The Wind

[mijhim]

how can energy equations be applied in analyzing how is DDWFTTW- Directly Downwind Faster Than The Wind- system works?
Thank you

 

[A.T.]

Check out this paper, chapter (2.1) and (2.3):
http://orbit.dtu.dk/fedora/objects/orbit:55484/datastreams/file_3748519/content

 

[russ_watters]

The key is being very clear and consistent about what frame of reference you are analyzing it from and recognizing that constant speed motion requires no force (so any net force will cause an acceleration).

 

[A.T.]

This question was part of the American semi-final for the International Physics Olympiad. The solutions are now online (page 11):

http://www.aapt.org/physicsteam/2013/upload/E3-1-7-solutions.pdf

 

[pmacias]

for your question. The concept of Directly Downwind Faster Than The Wind (DDWFTTW) has been a topic of scientific interest and debate for many years. In this system, a vehicle is able to travel downwind faster than the wind itself, seemingly defying the laws of physics.

To understand how this is possible, we can apply energy equations to analyze the system. Energy equations, specifically those related to kinetic and potential energy, can help us understand the forces at play in this system.

First, let's consider the energy of the wind. Wind is a form of kinetic energy, which is the energy of motion. The wind is pushing against the vehicle, providing a force that helps it move forward. This force is known as the aerodynamic force and can be calculated using equations such as the drag equation.

Next, let's look at the energy of the vehicle. The vehicle also has kinetic energy, but it also has potential energy due to its height above the ground. As the vehicle moves downwind, it is also moving downhill, which means it is converting potential energy into kinetic energy. This helps the vehicle maintain its speed and even increase it.

Furthermore, the design of the vehicle itself plays a crucial role in the DDWFTTW system. The vehicle must be designed in a way that minimizes drag and maximizes its ability to convert potential energy into kinetic energy. This can be achieved through the use of lightweight materials, streamlined shapes, and efficient propellers.

Overall, energy equations can help us understand how the DDWFTTW system works by showing how different forms of energy are converted and utilized to propel the vehicle forward. While it may seem counterintuitive at first, the laws of physics are not being violated in this system, but rather cleverly applied to achieve a seemingly impossible feat.