What's true for bullets, however, is not true of some other things that you might "shoot" from the front of the train. A great example is sound waves . If you turn on the stereo in your living room, sound waves "shoot out" of the speaker at the speed of sound -- something like 700 mph. The waves propogate through the air at that fixed speed, and they can go no faster. So if you put a speaker at the front of the 1,000 mph train, the sound waves will not depart the train at 1,700 mph. They cannot go faster than the speed of sound. This is the reason why planes traveling faster than the speed of sound create sonic booms .
Connecting the positive terminal of each battery to the negative terminal of the other battery will result in a huge surge of electrical current between the two batteries. This will cause the batteries to heat very quickly, and in lead-acid type batteries -- the most common type -- it will result in the generation of a large amount of hydrogen gas within the charged battery. The heat can melt internal and external battery parts, while the pressure from the hydrogen gas can crack the battery casing. Once the casing is cracked, escaping hydrogen can potentially ignite and explode.
Government employees sometimes reveal classified details accidentally in casual conversations and media interviews. We may not hear about it because it’s not in the interviewee’s or employee’s interest to point it out after the fact, or he or she may not even realize it at the time.... A former colleague of mine who was a retired CIA analyst used to tell his students he would never knowingly, but almost certainly would inadvertently, share a tidbit of classified information in the classroom. It is very difficult to remember many “smaller” details that are sensitive.