8th grade 4th Qtr Assessment

2 students were given identical sets of rocks. Each student grouped the rocks in a different way. Which is the best reason for this?

• 1 student group the rocks incorrectly

• each student grouped the rocks according to different factors

• the rocks in 1 set were larger than the rocks in the other set

• with so few rocks, it was impossible to form any kind of grouping

how are accurate models for the motions of objects in the solar system developed?

• scientists follow a fixed set of steps for developing a solar system model

• older data about the solar system are not considered as part of the process

• knowledge gained from studying one part of the solar system is applied to another

• models of the solar system shoudl fit only the observations that are already known

Early Egyptians thought the solar system was a rectangular box. People in early Greece pictured the universe as a set of cyrstal-like spheres. Later the solar system was viewed as a set of planets orbiting the sun. Why has the model of the solar system changed over the centuries?

• scientists preferred newer models

• new evidence caused revisions

• the newer models were easier to draw

• the information was finally put in books

• record observations

• show qualitative data

• present quantitative data

• complete calculations

• A

• B

• C

• D

• a

• b

• c

• d

Organisms can live on Earth because of Earth's location in the solar system. How does Earth's distance from the Sun most affect Earth's water and enable life to exist?

• It permits liquid water

• it allows water to freeze

• it changes water's specific heat

• it allows water to be salty or fresh

1 characteristic that is unique to water is that it

• has a low specific heat

• can be changed from a liquid to a solid

• dissolves very few substances

• exists naturally in 3 states on Earth

The greenhouse effect is a natural process that warms the Earth's surface. When the Sun's energy reaches the Earth's atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases. A greenhouse is used to model this phenomena. Which of the following cannot be demonstrated by the model?

• energy is used to evaporate water

• changes in the greenhouse gases

• light energy trapped as heat energy

• energy that builds up in the greenhouse air

Scientific models are very common. For which purpose below would a physical model be least helpful?

• simulating scientific phenomena

• simplifying a complex idea

• allowing visualization

• displaying data