AST Ch.7 Earth
List the different layers of Earth's atmosphere.
1. 0~12 km -- troposphere --where we live and where weather occurs 2. 12~50 km -- stratosphere 3. 50~80 km -- mesosphere 4. 80~100 km -- ionosphere
What is the six sections of the Earth?
1. Core---where the hot, dense materials resides. (inner core, outer core) 2. Mantle---approximately 3000 thick, mainly liquid rock 3. Crust---this is where we live and it also includes the seafloor 4. Hydrosphere---the oceans that comprise around 70% of the surface 5. Atmosphere---around 100 km in height, subdivided into several layers 6. Magnetosphere---zone of charged particles contained by Earth's magnetic field
What are the components of Earth's atmosphere?
79% Nitrogen, 20% Oxygen, 0.9% Argon, Carbon dioxide 0.03%
What kind of machine can detect seismic waves?
A seismograph.
As the increasing of altitude, what will happen to the atmospheric density and pressure?
Atmospheric density and atmospheric pressure decrease rapidly as the increase altitude.
Why the large aircraft try to fly in the lower parts of the stratosphere?
Because the convection ceases at the top of troposphere, so the lower part of stratosphere is more peaceful and safe.
Why the AM radio stations can be heard over great distances?
Because the top of ionosphere is full of electrons which act like a reflective blanket that can reflect the signals of Am radio station.
What decrease the ozone layer?
CFC decreases the ozone layer.
What is convection?
Convection is the constant flow of air within the atmosphere where the less dense warm air rises above the more dense cool air. This helps crate the surface of Earth winds and weather.
What is responsible for driving the plates?
Convection. When we go deeper into the ground, the warmer is gets. This is the ideal setup for convection---cool material on top of warm material.
What is lithosphere?
Crust and upper mantle.
What is the direction about magnetosphere?
From north to south.
How can tides benefit human beings?
Human beings use the fluctuation of tides to make electricity. This is called hydroelectric energy and it is not always related to massive dams.
How can the differentiation be possible on Earth?
If we believes that early Earth was molten. As with any liquid body, the denser object will sink to the bottom.
What is the four regions inside the Earth?
Inner core, outer core, mantle, and crust.
What is Van Allen belt used for?
It is used to store the charges from the sun.
What will happen when neutral and charged particles go through Earth's magnetosphere?
Neutral particles will pass through while charged ones get captured.
How can high tides happen on opposite sides of the Earth at the same time?
On the side of Earth closest the Moon, the ocean is pulled slightly toward the Moon. On the opposite side of the Earth, the water is left behind while the curst moves. This is how high tides happen on opposite sides of Earth at the same time.
Where is ozone layer?
Ozone layer locates at the top of the stratosphere and bottom of the mesosphere.
What is the function of ozone layer?
Ozone layer shields Earth from harsh particles coming from space.
How can aurora form?
Particles sometime escape and enter our lower atmosphere. They collide with air molecules. The molecules become excited and emit the light. This is known as aurora borealis and aurora australis.
What is the name of study of Plates move?
Plate tectonics.
What are responsible for mountains, ocean trenches, and other features?
Plates.
What are two conditions to have magnetosphere?
Rapid spin and liquid core.
How can scientists know what is inside the Earth?
Scientists know the speeds at which the waves travel depend on the material through which they are traveling through. Knowing the time and the distance to the source, scientists are able to calculate the density of the material in Earth's interior.
What is the density of the Earth?
The density of the Earth is 5500 kg/m^3.
What is tidal bulge?
The gravitational attraction between any two bodies is larger if the distance that separates the bodies is smaller. So, the gravitational pull of the Moon is larger on the side of the Earth that faces the Moon. This 'unevenness' is called tidal bulge.
How do tides form?
The gravitational influence of the Moon and the Sun on Earth.
What is in inner core and outer core?
The inner core is a solid, while the outer core is a liquid.
What makes our atmosphere unique?
The large presence of oxygen makes our atmosphere unique.
What is the radius of the Earth?
The radius of the Earth is 6400 km.
As the increasing of altitude, what will happen about temperature inside stratosphere?
The temperature within the stratosphere actually increases as you gain altitude.
What is tide?
Tide is a daily fluctuation in ocean level. There are two low tides and two high tides per day.
What is the name of regions that contain high energy in Earth's magnetosphere?
Van Allen belt.
List the phenomenon that shows the geologic activity on Earth.
Volcanoes, Earthquakes, geysers, hot springs.
