# Force on dog's head out of car sunfoof

• Automotive
• oneshortplanck

#### oneshortplanck

(i have made this thread as i previously had it in the aero section and it was probably not getting the attention such an important question deserves.)

lets use the sunroof as an example for simplicity.
what force is the wind acting on the dog at 50mph/22.3m/s?
therefore frontal area of dog head is 0.0314m^2
Drag coefficient = 2
air density = 1.22

0.00256 * 50 * 50 = 6.4 lb/ sq feet = 306.4Pa

0.0314 * 306.4 * 2=19.25N

here is my attempt (2) based on drag equation
2 x ((1.22 x 50^2)/2) * 0.0314 = 19N

any thoughts

Yayyy! They're approximately equal.

But both equally wrong unfortunately! You need to use the correct units in the drag equation, mph won't do. Also, 2 for Cd seems high for a dogs head, where did you get that from?

The tongue flapping contributes to an anamalous CD value.

billy_joule
billy_joule said:
But both equally wrong unfortunately! You need to use the correct units in the drag equation, mph won't do. Also, 2 for Cd seems high for a dogs head, where did you get that from?

the first is correct units, but the second should read
2 x ((1.22 x 22.352^2)/2) * 0.0314 = 19N

yes, i agree on the 2 cd, perhaps its the engineering factor of safety.

## 1. What is the force on a dog's head when it is sticking out of a car's sunroof?

The force on a dog's head when it is sticking out of a car's sunroof is dependent on several factors, including the speed of the car, the size and weight of the dog, and the aerodynamics of the car. Generally, the force increases as the speed of the car increases.

## 2. Can the force on a dog's head out of a car sunroof be harmful?

Yes, the force on a dog's head out of a car sunroof can be harmful. If the force is too strong, it can cause injury or even death to the dog. It is important to keep the dog safely inside the car while driving.

## 3. How can I calculate the force on a dog's head out of a car sunroof?

The force on a dog's head out of a car sunroof can be calculated using the formula F = ma, where F is the force, m is the mass of the dog, and a is the acceleration of the car. However, there are many other factors that can affect the force, so it is difficult to determine an exact calculation.

## 4. What precautions should I take to prevent harm to my dog when driving with the sunroof open?

To prevent harm to your dog when driving with the sunroof open, it is important to keep the dog safely secured inside the car. This can be done by using a dog seatbelt or a secure carrier. Additionally, it is important to drive at a safe speed and to avoid sudden movements that could increase the force on the dog's head.

## 5. Are there any laws or regulations regarding dogs sticking their heads out of car sunroofs?

There are no specific laws or regulations regarding dogs sticking their heads out of car sunroofs. However, it is important to follow traffic laws and drive safely to ensure the well-being of your dog and other drivers on the road. It is also important to check with your local government for any specific regulations regarding pets in vehicles.