three small but pleasant jokes…
Two atoms were walking across a road when one of them said, “I think I lost an electron!” “Really!” the other replied, “Are you sure?” “Yes, I ‘m absolutely positive.”
Albert Einstein was just about finished his work on the theory of special relativity, when he decided to take a break and go on vacation to Mexico. So he hopped on a plane and headed to Acapulco. Each day, late in the afternoon, sporting dark sunglasses, he walked in the white Mexican sand and breathed in the fresh Pacific sea air. On the last day, he paused during his stroll to sit down on a bench and watch the Sun set. When the large orange ball was just disappearing, a last beam of light seemed to radiate toward him. The event brought him back to thinking about his physics work. “What symbol should I use for the speed of light?” he asked himself. The problem was that nearly every Greek letter had been taken for some other purpose. Just then, a beautiful Mexican woman passed by. Albert Einstein just had to say something to her. Almost out of desperation, he asked as he lowered his dark sunglasses, “Do you not zink zat zee speed of light is zery fast?” The woman smiled at Einstein (which, by the way, made his heart sink) and replied, “Si.”
And know you know the rest of the story….
Q: What is the simplest way to observe the optical Doppler effect?
A: Go out at and look at cars. The lights of the ones approaching you are white, while the lights of the ones moving away from you are red