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You asked:How do car batteries work? --- Ike, Charlotte, N.C.Marshall Brain answered:A car battery is based on lead-acid battery technology. This technology has been around for decades, it is relatively inexpensive, it is reliable even in the harsh e ...

You Asked:Marshall Brain Answered:That has got to be frustrating.Usually if it is an operating system or driver problem, you will get a blue screen or the computer will reset and reboot. But when it just turns off for no reason... let me give you two ...

You Asked:Marshall Brain Answered:If you look at the ingredient label for just about any kind of cheese puff, the first ingredient is corn meal and the second ingredient is oil. All of the other ingredients are in the coating.The basic idea is to tak ...

You Asked:Marshall Brain Answered:There are some gases that turn into liquids simply by compressing them at room temperature. Examples include butane, propane, carbon dioxide, nitrous oxide and The problem with nitrogen (and other gases like it, incl ...

You Asked:Marshall Brain Answered:The human head contains the So go grab two 5 pound bags of sugar or flour and hold them with one hand. Or think about a 10 pound bowling ball. It is a lot of weight perched up there on your neck, especially if you ar ...

You Asked:Marshall Brain Answered:If you have a normal sheet of notebook paper and you try to fold it in half multiple times, you probably cannot get it to fold more than 6 times. Maybe 7 if you are really strong. That maximum limit is caused by two ...

You Asked:Marshall Brain Answered:Why can't you make a snorkel that is longer than a foot? The problem has to do with the strength of your diaphragm muscle and the pressure of the water in the swimming pool.If you look at the problem in reverse, you ...

You Asked:Marshall Brain Answered:How does the crossing signal know that the train is coming? There are lots of ways that the sensing of the train could be accomplished. You could have a weight sensor or a big push-button switch in the track. You cou ...

You asked:Marshall Brain Answered:If you are a cannon ball and you jump into a pool of mercury, it would look like this:That happens because mercury weighs about 13.5 grams per cubic centimeter. Water, for comparison, weighs 1 gram per cc. So a 1-lit ...

You asked:Marshall Brain Answered:So we can ask, How long does it take the shuttle to reach an altitude of 100 kilometers?The solid rocket boosters burn for about Let's ignore the acceleration (So it takes approximately 150 seconds for the shuttle to ...

You asked:Marshall Brain Answered:If you want to buy a small gas turbine engine, this page can be helpful: But if you want to pursue the DIY option, many people get started in gas turbine creation using an old A basic jet engine has three parts: a co ...

In many parts of the world, leeches are surprisingly common. You can find them in Amazon jungles, but you can also find them in the local lake. They can be found in swimming in water or crawling on land. For example, if you jump to the 40-second poin ...

You AskedMarshall AnsweredThe basic idea used to create a jigsaw puzzle in a factory is die cutting. You can see the die cutting process in this video:But if you want to make a jigsaw puzzle at home, you can use a jigsaw (also known as a scroll saw), ...

You AskedMarshall AnsweredThe thing to notice is the spinning disk below the dials. The disk is moving slowly in this video - about one RPM. In most common electric meters in the U.S., it is the rotation of this disk that lets the electric company me ...

You Asked:Marshall Answered:Meanwhile, real human beings seem so be stuck with bulky compressed air tanks or The gills of a fish work a lot like your There is such a thing as "artificial gills" that mechanically extract oxygen from water fo ...

You Asked:Marshall Answered:...have a lot more body hair than others?As described on So your arm hairs have much shorter growth phases than your head hairs do. In most people, that keeps arm hair relatively short. But not in all people. Some people c ...

Icynene is a spray-on foam insulation that you can use to insulate a home. Typically it would be used during new construction because (as seen in the videos below) in needs to be sprayed on like paint before the sheetrock goes on. The advantages clai ...

You Asked:Marshall Answered:A As a general rule:1) You can charge and discharge a capacitor much more quickly than you can a battery. The chemical reactions in a battery take time.2) A capacitor doesn't really "wear out", while a battery do ...

You Asked:Marshall Answered:Let's say that you want to make salt from salt water. You can simply put salt water on the stove and boil it. The salt is completely unaffected by heat, so it doesn't matter how fast you boil it. Eventually all the water i ...

You Asked:Marshall Answered:So how do gray squirrels find all the buried nuts? As described in the article, they don't find a lot of them. To be more specific, How do gray squirrels find the nuts that they bury? Obviously, in most cases, they do not ...