Physics Chapter 1 Homework Earths Surface Within The Oceans And Underground

AN INTRODUCTION TO GEOLOGY 1

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LEARNING OBJECTIVES/FOCUS ON CONCEPTS

1.1 Distinguish

1.2 Summarize

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1.3 Discuss

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TEACHER RESOURCES

Teaching 100-level Geoscience Courses

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ANSWERS TO QUESTIONS IN THE CHAPTER:

CONCEPT CHECKS

1.1

1. Physical geology is the study of materials composing the Earth (minerals, rocks, water, etc.)

and the processes that operate upon and below Earths surface (plate tectonics, rock

formation, deformation, erosion, etc.). Historical geology aims to understand the origin of the

Earth and its development through time. This study establishes an orderly chronological

arrangement of events and changes of the geologic past by study of the origin of rocks, the

movements of plates over time, and the occurrence of ancient environments and life forms as

displayed in the geologic record. These two areas of study are subdivided into many more

Humans can also exacerbate natural Earth processes, creating hazards, by interfering with

natural processes. Examples include the increased flooding hazards created by the clearing of

resources include water, soil, metallic and nonmetallic minerals, and energy. The extraction

opinions of how the natural world worked. These ideas were viewed as authoritative

explanations for many centuries, slowing the progress of study based on observations, until

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3. Today, the age of Earth is put at about 4.6 billion years. This age is based on scientific study of

the radioactivity of rocks, as will be discussed in Chapter 9.

4. An understanding of geologic time is essential to geologic study because many processes

studied are so gradual that vast spans of time must pass before noticeable and significant

changes occur. For example, the rocks of the Grand Canyon (Figure 1.5) were created over

millions of years, and it took many more millions of years for the Colorado River to erode down

it cannot be tested, it is not scientifically useful. Hypotheses may be accepted when evidence

demonstrates that they are correct, but also may be rejected when they fail rigorous testing.

The Earth-centered model of the universe is an example of a hypothesis that, once tested, was

rejected as an explanation of the orientation of our planet in the solar system.

A scientific theory is a well-tested hypothesis that has gone through extensive testing and

scrutiny. It is a well-tested and widely accepted view that the scientific community agrees best

explains a natural phenomenon. Theories generally include several well-tested, accepted

hypotheses to explain a larger scale process or phenomenon on Earth. An example of a theory

based on observations at the surface of Earth, but was not tested. As more data was collected,

and technology progressed to allow more detailed study of the Earths surface, this hypothesis

transformed into the well-tested, widely accepted Theory of Plate Tectonics, a theory that links

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hydrosphere via the water cycle through processes such as evaporation, transpiration, runoff,

precipitation, and infiltration.

The atmosphere is the gaseous layer surrounding Earths surface. This layer comprises the air

we breathe, protects Earth from harmful ultraviolet radiation, and creates the weather and

climate we experience at the surface.

The biosphere is all life on Earth. The biosphere includes plants and animals living on and

above Earths surface, within the oceans, and underground.

The geosphere is the solid earth extending from the surface to the center (core) of Earth

including both consolidated (rock) and unconsolidated (sediment) earth material. The

geosphere includes rock and sediment at the surface, bedrock beneath and at the surface, and

the materials making up the layers deep within the Earth.

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3. Increased rainfall in an area, a process of the atmosphere and hydrosphere, can affect other

Earth systems. The increased rainfall can affect the geosphere by triggering massive debris

flows (movements of unconsolidated earth materials downslope) and flooding (running water

overflowing natural channels) that erode the surface. These events in turn affect humans,

plants and animals by displacing the solid earth, impacting homes and businesses and

altering ecosystems.

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b) The bulb in the light is not working (needs to be replaced).

c) The electricity in the room is not working.

Once we have formulated our hypotheses, we should begin testing them. For our first

hypothesis and our last hypothesis, we could have an electrician test the power at the switch

and in the room to see if it is functioning properly. For our second hypothesis, we might try to

replace the lightbulb with a new one, and retry the switch.

is 314 mb; this is roughly 31% atmosphere at the top of Mount Everest. Therefore, we

would need to take about 3.2 breaths (31% * 3.2 = 99.82%) to equal one breath at sea

level.

answer, subtract 200 mb from 1000 mb and divide by 1000 mb to get the fraction of

air at this altitude. Multiply your answer by 100 to get a percent: 1000 mb  200 mb =

800 mb / 1000 mb = 0.80 * 100 = 80% of the atmosphere is below a jet traveling at 12

km altitude.

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7. Jupiter:

Figure 3 on page 23 tells us that 1 AU equals150 million (150,000,000) kilometers. To

determine the number of kilometers between Earth and Jupiter:

5.3 AU x 150,000,000 km = 795,000,000 kilometers

If we are traveling 1000km/hour (kph), to determine how long it would take to travel

795 km:

795,000,000 km / 1000 kph = 795,000 hours

We can convert this to days:

795,000 hours / 24 hours per day = 33,125 days

It would take us 33, 125 days to reach Jupiter in a jet plane!

We do the same calculations for Neptune, using 30 AU instead. Here, we get an answer

of 4,500,000 hours, or 187,500 days.

sediment. The resulting sediment will eventually be transformed into sedimentary rock at the

surface, thus accounting for a large percentage of all rocks.

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