Science experiments are a fun way for kids to learn all about science.I will introduce a few great experiments and teach your child all about the wonders of inertia(惯性).

You'll need some coins, at least eleven, and a smooth table.Stack(堆叠) all but one of the coins on the smooth table, making sure that the “high rise” is straight. Coins with wide edges make this experiment easy to do. Flick ( 弹 ) the extra coin quickly towards the bottom of the stack so that it hits the bottom coin.The bottom coin from the stack should shoot out from under the other coins without changing the rest of the stack. With good aim and quick flicks of your finger, you should be able to shoot all of the coins out of the stack one by one. Because the inertia of the stack of coins is so great, the force from the flicked coin is not enough to make the entire stack move or fall down.

Place a narrow piece of paper on a smooth table. Hold the paper so that most of it hangs off the table.Place a pencil on the paper so that it is standing straight.Now,slowly try to pull the paper out from under the pencil.What happens? Set up the paper and pencil again, and give the paper a fast pull. What happens to the pencil this time?

Since the still pencil wants to stay at rest, it will be against the fast movement of the paper.This means that when the paper is moved quickly out from under the pencil, the pencil remains standing straight. If the paper is moved slowly, the movement has a chance to influence the pencil, and it will fall down.

When you watch TV programs about wild animals, it is surprising to see how an antelope (羚羊)can run away from a strong lion. In the wild, everyone has his own way to protect himself. Even plants have their own ways to fight against enemies.

Over millions of years, plants have developed their own way to protect themselves. Chemicals (化学物质) are used by plants to live. By making their leaves, flowers, roots and fruits poisonous (有毒的) to enemies, plants can fight back.

One such plant is the Golden Wattle tree. The British scientist David Cameron has found when an animal eats the tree’s leaves, and the number of poisonous chemicals becomes more in the other leaves. “It’s like the injured (受伤的) leaves telling the others to fight against the enemy together, ” he said.

The tree also sends messages to plants near it by giving out a special smell. Golden Wattle trees in the nearly 45 meters will get the message and produce more poison in 10 minutes. Now, if an enemy eats too many of the trees’ leaves, he will die.

Every kind of plant is good at producing special chemicals. Animals that feed on plants or glass, like rabbits, can safely eat the leaves of one tree, but they may be hurt by its neighbor.

In this way, plants have not only developed their own way to protect themselves, but also shared it with others. So it’s impossible for a single animal to damage even a small area of forest.

For introverts interacting with other individuals can be challenging. They need to go to a quiet place to gather their thoughts and recharge. 【小题1】 On the other hand, extroverts are highly friendly and social. By their very nature, extroverts are well-loved, but that doesn’t mean introverts aren’t just as likable. Here are some reasons why you need introvert friends.

Introverts listen. In group discussions, if extroverts love to talk, introverts like to listen. This means introverts often hear more of what’s occurring around them. They catch all the things others miss.【小题2】

Introverts are highly creative. There’s evidence that an independent, quiet thought gives birth to more creativity compared to a big brainstorming group. Introverts spend tons of time in their heads.【小题3】And their minds are constantly imagining, remembering and analyzing, which leads to insights and creativity that can translate to inventive solutions and ideas.

Introverts are persistent and focused.【小题4】An introverted friend can help you. They don’t give up easily, and love working independently. They are willing to invest the energy and time required. They are less distracted by new possibilities and opportunities.

【小题5】They don’t use words lightly. Introverts are intentional and thoughtful. Thus when they do speak up in group settings, it’s usually worth your time to listen. This is a refreshing and valuable quality.

Introverts make good friends. An introvert’s ability to listen, natural persistence, and desire for deep relationships can produce devoted friendships. They make trusted, safe friends.