Test Review:
- Will a dry sponge have the same density as a wet one? Explain.
No, the wet one will be denser, because it will have more mass per volume.
- How can you determine if something will sink or float in water?
If the objects density is greater than 1, it will sink, if its density is less than 1, it will float.
5. List the MAJOR layers of the Earth from the outside to the center. Crust, Mantle, Outer Core, Inner Core
6. What is the difference between the composition of the lithosphere and the asthenosphere?
Lithosphere is solid rock and the asthenosphere is “plastic-like” hot rock.
- How do scientists know what the inside of the Earth is made of? Describe in detail. (hint: your answer should say something about the “shadow zone”)
Scientists use the changes in speed and direction of seismic waves to determine the inside of the Earth. S-waves stop at the outer core (true liquid layer) and p-waves will slow down and bend. Both of these waves behavior end up creating the shadow zone on either side of the focus on the opposite side of the Earth, where no waves are detected by a seismograph.
- What causes an earthquake to occur? Where do most earthquakes occur in the US?
An EQ occurs due to the breaking and/or shifting of rock beneath the Earth’s surface.West coast and where fault lines are present.
- Can Earthquakes be predicted? Why or why not?
No, there is no way to know exactly when the rock will break/shift, but scientists can use past data to identify high risk locations.
- Describe how scientists measure earthquakes (Richter scale vs. Mercalli Intensity Scale)
The Richter scale is measured by magnitude (energy released) and the Mercalli scale is measured by damage/intensity.
- List 3 ways to make our cities architecture more earthquake-safe.
Moorings, steel reinforcements in walls, sturdy foundations, bridges that are able to move with the earth, etc.
- HONORS ONLY- How can you determine the epicenter of an earthquake/what information do you need?
Find the time difference between the p and s waves for 3 stations, use the time travel graph to determine the distance to the epicenter from each station, draw circles around each station with the distance being the radius, and find where all circles intersect.
Explain the differences in finding the density of a block, marble and penny.
Block: Find the mass with a triple-beam balance. Find the volume by multiplying the length x width x height. Divide mass by volume.
Marble: Find the mass by placing the marble in a cup, subtract out the cups mass. Find the volume using the “volume by difference” method in a graduated cylinder. Divide mass by volume.
Penny: Find the mass using a triple-beam balance. Find the volume using the “volume by difference” method in a graduated cylinder. Divide mass by volume.
Compare and Contrast p, s, and surface waves. (shape, speed, what they can travel through, etc)
P-waves: Move back and forth parallel to the direction of the wave (slinky), fastest wave, and can travel through liquids and solids.
S-waves: Move at right angles to the direction of the wave (rope), 2nd fastest wave, and cannot travel through liquid, only solid.
Surface waves: Slowest wave and cause the most damage. Only travel on the surface of the Earth.