With the latest post being on elasticity I have decided that that shall be the topic of the next physics page I write. The mechanics of stretching is very complicated especially when considering real materials that are never perfect in their qualities. Since this topic comes up reasonably often I think it will be a good one to cover next. There is also something else I would like to talk about. There is a joke question that goes along the lines of asking someone if they would purchase something they couldn’t or weren’t allowed to see first. When the person assents to the negative pointing out to them that they will almost certainly be purchasing electricity makes the point very clear. Despite being frivolous this joke raises an interesting question. How can we know electricity is real. We get told its real and because electrical appliances don’t work when not plugged in we assume it must be true. One of the most practical ways is to observe electricity ourselves. By wiring multiple batteries through a thin wire we should be able to observe it glow and warm up meaning energy is being transferred to it. The only way we can be sure is to perform an experiment for ourselves.
More so in America then Europe global warming is a contentious issue. Conspiracy theorists from both sides can claim that the other is faking and editing evidence for nefarious ends and so a good way for the general public to cut through any deception is to perform an experiment for themselves. An experiment I designed for this goal is this: First get a tub of water and take a sample. Add universal indicator to the sample and depending on region it should turn green or very very light yellow. Now take a pipe and attach it to a car exhaust. With the other end of the pipe in the tub of water turn the car engine on. With the fumes bubbling through the water take a sample of water every fifteen minutes. If the environmentalists are correct then the samples should turn progressively more orange the later on they are taken. The independent variable is time of exposure to pollutant. The dependent is pH of water. All experiments should have two things you believe are connected, and then change one to see if change occurs in the other. Using this basic framework almost all hypotheses can be tested by anyone, anywhere.