FREE WCAS Earth and Space Science Questions and Answers

Question 1

Many different energy sources are used to produce electricity. The Amount of Carbon Dioxide Released graph shows the amount of carbon dioxide gas released by some energy sources, in grams per kilowatt hour (g/kWh).

Which change in energy sources would cause the greatest decrease in the amount of carbon dioxide released?

Accepted Answer

Increasing hydroelectric and reducing coal

Answer

Explanation:
Hydroelectric power also produces electricity with very low carbon dioxide emissions, whereas coal is one of the highest emitters of carbon dioxide among energy sources. Thus, increasing hydroelectric power and reducing coal would likely result in the greatest decrease in carbon dioxide emissions.

Question 2

A student stood quietly in a field observing a rabbit eating grass. The student moved and stepped on a twig. The twig broke, which made a loud sound, and the rabbit ran away.

Choose the order that shows how a rabbit processes information after hearing a twig break.
1 - The rabbit hears a twig break.
2 -
3 -
4 -

A. The rabbit acts.
B. The rabbit's brain processes information.
C. The rabbit's brain sends a message to act.

Accepted Answer

BCA

Answer

Explanation:
The sequence of events goes from the initial perception of the sound by the rabbit's ears, to the processing of this information by its brain, to the brain sending a signal to the muscles to act, and finally to the rabbit's physical response of running away.

Question 3

From November to February, the constellation Orion is clearly visible in the night sky from Mississippi. Orion appears to rise from the east and set in the west. The stars do not actually move through the sky. They appear to change positions due to the Earth's Movement.

What factor is responsible for the changes in Orion's position when viewed during the winter month?

Accepted Answer

The rotation of Earth on its axis

Answer

Explanation:
As the Earth rotates on its axis, different parts of the sky become visible from different locations on the planet. This rotation causes celestial objects, such as stars and constellations like Orion, to appear to move across the sky from east to west. So, as the Earth rotates during the night, it gives the impression that Orion rises from the east and sets in the west. This apparent motion is due to the observer's perspective from the rotating Earth, not due to the stars actually moving.

Question 4

Which celestial body is primarily responsible for causing ocean tides on Earth?

Accepted Answer

Moon

Answer

Explanation:
The gravitational pull of the Moon is the primary force behind ocean tides on Earth.

Question 5

What type of eclipse occurs when the Moon passes directly between the Earth and the Sun?

Accepted Answer

Solar eclipse

Answer

Explanation:
A solar eclipse occurs when the Moon blocks the Sun's light from reaching Earth.

WCAS - Washington Comprehensive Assessment of Science Practice Test

WCAS - Washington Comprehensive Assessment of Science Practice Test

FREE WCAS Earth and Space Science Questions and Answers