How does a Maglev train work? They use magnets to move the train forwards and to reduce friction. Maglev is the shortened form of magnetic levitation, and it is a train based on the principle of magnetic attraction and repulsion. We all know that when you have two magnets, the opposite poles attract each other […]
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Why does ice have so little friction? Because there is a very thin layer of water on top of the ice. Although, the reason for that is not completely understood. If a force is applied to an object it picks up kinetic energy. The kinetic energy is transferred from the energy used to make the
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Why are emulsifiers used in processed food? They help different compounds to combine, and they make foods less sticky and easier to eat. What are emulsifiers? Their basic job is to combine two compounds that wouldn’t normally be able to hold together. An obvious example is oil and water. If you tip olive oil into
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What are stalagmites and stalactites? They are deposits of minerals that form in caves. Stalactites hang down from the top of the cave and stalagmites rise up from the ground. To help you remember, stalactites have a “c” for ceiling and stalagmites have a “g” for ground. If you want another way to remember which
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What is CRISPR? It is a way of editing genes and it stands for Clustered Regularly Interspaced Short Palindromic Repeats. It works by separating the genes inside the DNA and inserting a mutation. To begin with, let’s look at what DNA and genes are. DNA is inside all of our cells and it holds the
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Why does time go forward not backward? Because of entropy. Entropy is the measure of how random and dispersed the energy and mass in a system are distributed. It is described by the Second Law of Thermodynamics, which says that the entropy of a closed system increases over time. The system has to be closed
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Is a force field possible? In theory, there are several possibilities, such as warping space time, electric fields, directional lasers, a controllable plasma, a magnetic field, and others. We have all seen science fiction movies where a spaceship is protected by a forcefield that destroys enemy fire when it comes into contact. The recent movie
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What is the pH scale? It probably stands for potential of hydrogen and it shows how much hydrogen is in a substance. The pH scale is written with a capital H because the symbols for the elements are always written with a capital. However, when the scale was invented by a Danish chemist called Soren
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Why do we sneeze? We usually sneeze in order to remove an irritant from the nose. There are many different things that make people sneeze, but the most common cause is when there is an irritant in the nose. This could be smoke particles, it could be dust, it could be anything. The nose is
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Why does iron rust? The iron atoms react with oxygen molecules to produce iron oxide, which is rust. Other metals don’t rust because only iron, or metals with an iron alloy can rust. This is because rust is iron oxide. Other metals can react with oxygen in different ways or corrode, but only iron can
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