How did the Black Death change society? It ended serfdom and slavery, improved worker conditions, brought a recession, harmed religion, increased antisemitism, improved medical practice, improved women’s rights, and changed the world of art and fashion. There were three major plagues, but let’s look at the middle one, the one that is most famous. It […]
#344 How did the Black Death change society? Read More »
How did the Black Death spread? It was spread by people along trade routes. The Black Death is another name for bubonic plague, which is caused by a bacteria called Yersinia pestis. Y. pestis generally lives in fleas that feed on rats. When the flea bites the rat, the bacteria passes into the rat’s blood.
#343 How did the Black Death spread? Read More »
How does a parachute work? A parachute works because of air resistance. If you jump out of an airplane, presuming you are high enough, you are going to accelerate until you reach terminal velocity. Terminal velocity is the maximum speed an object can attain when falling through a fluid. And here is the point that
#341 How does a parachute work? Read More »
How much blood can you lose? Well, obviously all of it. How much blood can you lose and still function? Depending on your body size, from between 15 to 30%. We have approximately 5 liters of blood in our bodies, but that varies by size. An average-sized female of 165 cm will have about 4.3
#340 How much blood can you lose? Read More »
Why is PM 2.5 dangerous? They are particles that are too small for our nose to catch. PM stands for Particle Matter and they are microscopic solid or liquid particles that are small enough and light enough to be suspended in the air. There are many sources of these particles. In some countries, one of
#337 Why is PM 2.5 dangerous? Read More »
Why are diamonds so expensive? Because we believe they should be expensive, not because they are rare. We think that diamonds are expensive because they are rare, but they are not as rare as we think. Diamond is a structure made of carbon atoms that are arranged in a crystal structure. Diamond is one of
#336 Why are diamonds so expensive? Read More »
How do fossils form? They form when the bones of an animal are turned to mineral. A fossil forms when an animal dies in water or falls into water. This water is more commonly an ocean or a lake because for a fossil to form, the sediment at the bottom of the water has to
#333 How do fossils form? Read More »
Do cyanide pills kill as quickly as in the movies? Perhaps. If it is the right kind of cyanide, it can kill in about 2 to 5 minutes. There are several different types of cyanides and they can be found in liquid, solid, or gas form. Cyanide is a group of chemicals that have a
#332 Do cyanide pills kill as quickly as in the movies? Read More »
Can we cover the Sahara Desert in solar panels? Technically, yes. Practically, no. The Sahara Desert is the largest hot desert in the world. It covers 9.2 million km2, which would make it the fifth largest country in the world, if it were a country. It is one of the most exposed areas on Earth
#330 Can we cover the Sahara Desert in solar panels? Read More »
Why do we get hot when we exercise? Because heat is a byproduct of the process muscles use to make energy. Let’s look at how we get energy to our muscles. We are unable to make our own energy, we can only convert one energy source into another. We have to eat plants or animals
#328 Why do we get hot when we exercise? Read More »
