Stopping distance = (speed 2) / (254 * skid coefficient)
Where:
- Stopping distance is measured in feet
- Speed is measured in miles per hour (mph)
- Skid coefficient is a measure of the friction between the tires and the road surface
Assuming a skid coefficient of 0.7, which is typical for dry pavement, the stopping distance for a car travelling at 30 mph can be calculated as follows:
Stopping distance = (30**2) / (254 * 0.7) = 8100 / 177.8 feet
Therefore, the stopping distance for a car travelling at 30 mph is approximately 45 feet.
It's important to note that the stopping distance can vary depending on factors such as the condition of the road surface, the type of tires, and the driver's reaction time. Therefore, it's always important to maintain a safe following distance and be prepared to brake if necessary.
