I learned this today. A touchscreen works because a tiny electric current is sent to your finger, which allows the device to calculate where your finger is. There are two different types of touchscreen: resistive and capacitive. The touchscreen in the phone you are probably reading this on is a capacitive touchscreen, so let’s look […]
#248 How does a touchscreen work? Read More »
I learned this today. Chloroform knocks people out by causing depression of the central nervous system. Chloroform appears to have been discovered by several people independently in 1830 and 31. A German pharmacist called Moldenhawer discovered it in 1830. An American physician called Samuel Guthrie, a French scientist called Eugene Soubeiran, and a German scientist
#241 Why does chloroform knock people out? Read More »
I learned this today. Bleaches react with colored organic compounds and turn them into colorless ones. Bleaches by working on the chromophore of a molecule. This is the part of the molecule that is responsible for the color we see. Our eyes do not see color. Our eyes detect a wavelength of light, which they
#240 How does bleach turn clothes white? Read More »
I learned this today. The Kola borehole is the deepest manmade borehole on Earth, and it is the deepest artificial point on Earth. The Kola borehole is on the Kola Peninsula, which is on the Russian border with Norway. It is in the very far north of Russia and is in the Arctic
#225 What is the Kola borehole? Read More »
I learned this today. Hydraulic machines work because a force applied at one point to an incompressible fluid is transmitted to another point and multiplied at the same time. There are two principles at work in a hydraulic system. The first is that an incompressible liquid will transfer energy and the second is that
#222 How does a hydraulic system work? Read More »
I learned this today. Radar works by using radio waves to work out the position of objects relative to the detector and sonar uses sound waves. Radar works in a similar way to sonar, but it is far more effective in air. A sonar system sends out a sound and waits for the sound
#221 What is the difference between sonar and radar? Read More »
I learned this today. Deep sea fish can survive because they don’t breathe in the same way that we do. However, even they cannot survive at the very bottom of the ocean. Pressure at sea level is 14.7 psi (pounds per square inch). If someone weighing 14.7 pounds stood on you, you would
#219 Why don’t deep sea fish get crushed by the pressure? Read More »
I learned this today. The Trieste, a Swiss and Italian submarine reached a depth of 10,911m. This is the deepest point on Earth and is the Challenger Deep of the Mariana Trench. Different submarines can reach different depths, depending on what they are needed for. A submarine that is built to go deep
#218 How deep can a submarine go? Read More »
I learned this today. Bulletproof glass is made of two different types of laminated glass, one hard and one soft. Glass was invented in about 2500 BC, although only used as beads and jewelry. In 1450 BC, Egyptians started using glass drinking vessels. Plate glass was invented in about 1620 and glass production was
#217 How does bulletproof glass work? Read More »
I learned this today. Antimatter is matter made up of antiparticles. An antiparticle and a particle have the same mass but opposite electrical charges. A proton, for example, contains three quarks (2 up and 1 down), has a positive charge, and weighs 0.00000000000167262192 picograms. (A picogram is 100 billionth of a gram.) An
#216 What is antimatter? Read More »
