How does hydroelectric power work? Hydroelectric power works by converting the gravitational potential energy of stored water into kinetic energy, and then into electricity. As the first law of thermodynamics says, energy cannot be created or destroyed, only transformed from one type into another. This is what hydroelectric power does. A hydroelectric power station takes […]
#1411 How does hydroelectric power work? Read More »
What is the Sargasso Sea? The Sargasso Sea is the only sea in the world that doesn’t have any land borders. It is located in the Atlantic Ocean and has an area of 3.5 million square kilometers. That makes it roughly 3% of the Atlantic Ocean. The Sargasso Sea is bordered by four ocean currents.
#1410 What is the Sargasso Sea? Read More »
What makes a rainbow? A rainbow forms when light is refracted, reflected, and dispersed by raindrops in the air. The rainbow can only be seen from an angle of 42 degrees. The sun, or the source of light, must be behind you. We can see a rainbow because of the speed of light through an
#1409 What makes a rainbow? Read More »
What is a filibuster? Filibuster has two meanings that are connected. The original, historical meaning of the word filibuster, is someone who “engages in an unauthorized military expedition into a foreign country or territory to foster or support a political revolution or secession”. The more modern meaning of the word filibuster is political, and it
#1408 What is a filibuster? Read More »
What is the Dewey Decimal system? It is a system used to classify books in libraries, so that they can be found easily. It was created by Melvil Dewey in 1876. Libraries have existed since writing was first invented. Whatever was written needed a place to be kept in. However, libraries were not public. Clay
#1407 What is the Dewey Decimal system? Read More »
What did Florence Nightingale do? She managed to improve hospital hygiene, made nursing into a profession, used statistical analysis, and became the first female member of the Royal Statistical Society. Florence Nightingale was born in 1820. She was British, but she was born in Florence, Italy, during a family tour of Europe, hence her name.
#1406 What did Florence Nightingale do? Read More »
What is self-raising flour? Self-raising (self-rising in the US) flour is wheat flour that has the leavening agent (usually baking powder) and sometimes salt already added to it. The purpose of self-raising flour is to (as it says in the name) rise on its own, which means without adding any other ingredients. When you are
#1405 What is self-raising flour? Read More »
Why do some plants have thorns? Plants generally have thorns to deter herbivores and insects from eating them. Plants usually have parts that they want to be eaten (the fruit, for example) and parts that they don’t want to be eaten (the stem and leaves). Plants have different methods of scattering their seeds. Some do
#1404 Why do some plants have thorns? Read More »
When were the first colored cars? The first real colored cars became available in the 1920s, but before that, there was a choice of a few colors, although they had to be custom painted. When we go to buy a car these days, after we choose from the thousands of available models available, we then
#1403 When were the first colored cars? Read More »
What was the Texas Revolution? It was a fight by Texas for independence from Mexico. It led to the Republic of Texas, which didn’t last long before it was absorbed into the growing United States of America. Texas is the second largest state in the United States, coming after Alaska. It is roughly 40% the
#1402 What was the Texas Revolution? Read More »
