Invent a formula that can accurately detect the speed of a vehicle while standing on the side of the road. You will not know distance
To accurately detect the speed of a vehicle while standing on the side of the road without knowing the distance, we can utilize the concept of Doppler effect. The formula to calculate the speed of a moving vehicle based on the Doppler shift is:
Speed = (Change in Frequency × Wavelength) / (Original Frequency × cos(θ))
Where:
- Change in Frequency represents the difference between the received frequency and the original frequency of the sound wave emitted by the moving vehicle.
- Wavelength is the length of the sound wave emitted by the vehicle.
- Original Frequency is the frequency of the sound wave emitted by the vehicle.
- θ is the angle between the direction of the moving vehicle and the line connecting the vehicle to the observer.
However, it is important to note that this formula assumes the emitted sound wave to be unaffected by the vehicle's own velocity (which is usually valid in practice). Additionally, it assumes a known frequency of the emitted wave through other means (e.g., measuring the frequency of a stationary vehicle's sound beforehand).
By measuring the frequency difference between the emitted sound wave and the received sound wave, we can determine the change in frequency. Combining this information with the known wavelength and original frequency, we can calculate the vehicle's speed even without knowing the distance.
It's worth mentioning that this method requires an accurate measurement of the frequency difference and the angle θ. Utilizing advanced audio equipment or specialized Doppler radar systems can help in obtaining precise measurements for accurate speed detection.