How does a roller coaster work?

A roller coaster works the same way as a bicycle coasting down a hill. When you ride your bike to the top of a hill, you pedal to get there. Then, to coast down the hill, you take your feet off the pedals and glide down the other side. If the slope is steep enough, you can go very fast. Similarly, a roller coaster is only powered at the beginning of the ride, when the coaster, or train, is pulled up the first hill. When it goes over the top of the hill, the weight of the train itself, pulled downward by gravity, is what keeps the entire unit moving.

There are no cables that pull the train around the track. This conversion of potential energy (stored energy) to kinetic energy (the energy of motion) is What drives the roller coaster, which often reaches 60 miles (96.5 kilometers) per hour. Running wheels guide the train on the track, and friction wheels control the train’s movement to either side of the track. A final set of wheels keeps the train on the track even if it is upside down. Air brakes stop the car as the ride ends.

Is it true that a salmon will always return to its birthplace?

Yes, the salmon is most famous for its life cycle. It is born in tiny streams far from the sea, where it spends the first part of its life in freshwater. In the springtime, it migrates down streams to rivers, sometimes traveling hundreds of miles, until it ends up in the open ocean, where it spends much of its adult life. Then, when it’s time to lay its eggs, the salmon makes the journey back to its birthplace to spawn and die. The salmon’s body is rich in oils that are picked up during its life in the ocean. The oil helps give the salmon the energy it needs to navigate the journey upriver.

Posted on Categories General

Why do we call a leg injury a “charley horse”?

The phrase charley horse has its roots in baseball. At the beginning of the twentieth century, groundskeepers often used old and lame horses to pull the equipment used to keep the playing field in top condition.

The Baltimore Orioles had a player named Charley Esper, who, after years of injuries, walked with pain. Because his limp reminded his teammates of the groundskeeper’s lame horse, they called Esper “Charley Horse.”

Why does the body need vitamins and minerals?

Vitamins are chemicals that the body needs to function well; minerals are metals and salts that the body also needs in tiny amounts to run properly. Both help the human body grow. Different foods, like vegetables, contain different amounts of vitamins and minerals, so it is important to have variety in your diet so you can get a good balance. When it comes to vitamins, each one works differently in your body. Vitamin D in milk helps your bones grow; vitamin A in carrots helps you see at night; vitamin C in oranges helps boost your immune system and helps your body heal if you get a wound; and the B vitamins in leafy green vegetables help your body make protein and energy.

And although some vitamins like A (which helps your eyesight) and D are stored in your body (for several days or up to several months), others, like C and the B vitamins, quickly pass through your bloodstream. So it’s important to replace your vitamins every day.

Why are the Southern United States called “Dixieland”?

The nickname “Dixieland” didn’t come from the Mason-Dixon Line, the boundary between the free and the slave states. Rather it’s from the word dixie, which was what southerners called a French ten-dollar bank note of New Orleans that was already in use in 1859 when Daniel Emmet, a northern black man, wrote and introduced his song “Dixie,” which spread the South’s nickname and somehow became a battle song for the Confederacy.

Posted on Categories General

Why do we say that a victim of his own scheming has been “hoisted on his own petard”?

The phrase “hoisted with his own petard” is found in Shakespeare’s Hamlet. It has come to mean that someone has been or will be hurt by the very device he’s created to injure someone else. Hoist means to raise something into the air, while petard is an antiquated word for bomb. Therefore, if you were “hoisted on your own petard,” it means you were blown up by your own bomb.

Posted on Categories General

What does a mayor do?

The mayor-council is the oldest form of city government in the United States. Its structure is similar to that of the state and national governments, with an elected mayor as chief of the executive branch and an elected council that represents the various neighborhoods, forming the legislative branch. The mayor appoints heads of city departments and other officials.

The mayor also has the power to veto the laws of the city (called ordinances), and prepares the city’s budget. The council passes city laws, sets the tax rate on property, and decides how the city departments spend their money to make the city a better place.

When did the first flowers bloom?

Mosses and fungi probably appeared about 400 million years ago. By about 200 million years ago, the earth sprouted sweeping forests of giant cycads, conifer trees, huge horsetails, and ferns. But the first flowering plants did not appear until the dinosaurs, sometime in the middle of the Cretaceous period, about 100 million years ago.

Before this, most of the trees had been gymnosperms, or plants with cones. Magnolias are among the oldest of all flowering plants, appearing about this time, along with orchids. With flowers came many insects, including butterflies, ants, termites, and bees. The flowering plants provided food for these insects, who spread the pollen from flower to flower to produce the seeds that would keep the flowers reproducing.