If you live in the Washington D. C. metro area and love autos like I do then I assume you also employ signs and banners to get your message across. The reason I assume this to be the case is that Washington D. C. is a town where everyone is trying to get their message across. Moreover, if you are driving past a another person to whom you are trying to communicate you probably need a sign to communicate effectively because your voice will not be an efficient means of communication. This is the unfortunate situation because of a little thing called the Doppler Effect.
The Doppler Effect is defined as “an increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move toward (or away from) each other. For example, the effect causes the sudden change in pitch noticeable in a passing siren, as well as the redshift seen by astronomers.” Because of the Doppler Effect, the sound of your voice will sound distorted to the person to whom you are attempting to communicate as your car passes by them. This distortion might be enough to make the substance of your communication incomprehensible to the intended object of your communication. For this reason it would probably be more effective to communicate with this person through the use of signs and banners.
By using a sign to communicate your message to the person you pass in your vehicle you will be more likely to effectively communicate your message. I think the Washington D. C. metro area would definitely be a better place if we were all more effectively communicating our unique messages. I hardily believe this to be true because it can be frustrating to try to communicate and fail in the endeavor. Happy Holidays from all of us at the D.C. Auto Geek Blog!