Science Summary 2nd Semester for Grade 2

Science G 2 - Semester II (Page 111-157)

Energy gives us the strength to run.

A force is needed to push or pull something along and make it move.

Moving water is a force that can carry you down the river.

Sometimes we pull to make things go.

Magnet can hold things together. They can also pull on things to make thing move. Nail, paper clip, magnet and other magnetic things can a magnet move.

What do we call the “pull of the earth” is gravity.

Wheels help many things move?

Remember when you are playing a ball. Friction makes your ball stop rolling.

Rub your hands together quickly for 1 or 2 minutes. Then touch your hands to your face, how do your hands feel? Your hands will feel warmer.

Wind is moving air. We cannot see the air; we cannot taste or smell it, but it is there. That is the right opinion about the air.

The air made of a special group of gases that are mixed together in special amounts.

What would happen if the air were made only of carbon dioxide? People and animal will die.

Whenever the air moves, we have wind. Inside our house, we can make wind by using a fan.

Hurricane are windstorms that begin over the ocean. Tornadoes are windstorms that builds up over hot land.

The three things will always decide the weather is the sun, air and water.

Cold air is heavier than warm air. The water went back in to the air. We call this evaporation.

Where is the rain come from? It’s begin to fall when clouds, heavy with water from the air, meet cool air. Snow is the frozen water.

There is no sound on the moon. Even if someone shouts, it would not make a sound on the moon. Sound need materials (air, liquid or solid) to travel. Because there is no air in the moon, sound can not heard by anyone.

The sky is blue because because the sunshine through the band of air.  The sky is dark in outer because there is less air for the sun to shine.