The positive effects of a decision. Benefits are similar to “pros,” or advantages.
The process in which something ignites or bursts into flame.
The process that occurs when a gas loses energy (is cooled) and becomes a liquid.
The motion of a gas or a liquid in which the warmer portion rises and the colder portion sinks. This creates a circular motion.
This effect is seen when something moving in a straight line appears to curve because it is moving above a spinning surface. The motion will appear differently depending on whether it is observed from a stationary viewpoint or a rotating viewpoint. For example, someone who is still will see the object moving in a straight line. Someone who is on a rotating surface will see the object moving on a curved path.
The harmful or negative effects of a decision. Costs are similar to “cons,” or disadvantages.
The mass of an object divided by its volume.
A time when no rain or snow falls in an area that needs water. A drought may last for months or years.
A person who uses the process of technology to help people solve problems. Engineers develop tools and other objects to extend human limits. There are many types of engineers.
A branch of science and technology that is concerned with designing and building objects to help people solve problems.
The process that occurs when matter changes from a liquid into a gas.
An overflow of water onto land that is not usually under water.
A flat area next to a river. This area is the first place to be flooded when a river overflows its banks.
Material, such as coal, wood, or gas, that is used to produce heat or power. Fuel is one of the elements needed for a fire to continue burning.
The change in energy that is related to the change in temperature of a system. Heat is one of the elements needed for a fire to continue burning.
A large storm that may form over warm oceans. The winds are greater than 75 miles per hour. When a hurricane moves onto land, it may cause a great deal of damage from wind and water.
A colorless, odorless gas that makes up about one fifth of the air in the atmosphere. Oxygen is one of the elements needed for a fire to continue burning.
A pendulum is a system made of a mass attached to a supporting string. The mass is free to swing as it is affected by gravity.
Statements of probability indicate how likely it is that an event will occur. They do not indicate whether the event will actually happen.
The potential costs of making a decision.
An area that does not receive much rainfall each year.
The process that helps people solve problems. Technologies extend human limits to help people solve problems.
A violent storm that forms over a relatively small area of land. Tornadoes are the result of unstable atmospheric conditions. The winds of a tornado rotate in a funnel-cloud form and may blow hundreds of miles an hour. Tornadoes usually occur during severe thunderstorms.
The pattern of water movement on Earth. In the water cycle, water particles move from liquid to vapor and back to liquid again. The cycle occurs as water moves from lakes or oceans into the clouds. The water falls as rain or snow, and moves through the ground into creeks and rivers. It then travels back to lakes and oceans.
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Linking
Question Explore Linking
Question Explain Linking
Question Elaborate Linking
Question Evaluate
Key idea: Different designs are best suited for different situations.
Activity: Students express their ideas about the types of decisions that need to be made when designing a house. They then consider how those decisions might change if the house were to be built in a different location.
Key idea: Decisions about designs can affect their function.
Activity: Students construct a model house and test it to see how well it stands up to wind. They then refine their design before testing the model again.
Key idea: Decisions have both benefits and costs.
Activity: Students consider how costs and benefits influenced their model house design and then apply their ideas about costs and benefits to a new situation.
Key idea: Designers think about benefits and costs.
Activity: Students analyze the design of an object using a series of questions to guide their thinking. They then consider a mystery object to try to determine its function and the reasons behind its design.
Key idea: Designs for a product to help people protect themselves during a weather event need to consider both benefits and costs.
Activity: Students create a technology that will help solve a weather-related problem for people. They then write an advertisement and explain the reasons for the product’s design and the costs and benefits of the product.