1.
What is the least dense layer of the earth?
Correct Answer
A. Crust
Explanation
The crust is the least dense layer of the earth because it is composed of lighter materials such as rocks and minerals. The crust is the outermost layer and is relatively thin compared to the other layers. The mantle, outer core, and inner core are all denser than the crust due to the presence of heavier elements and metals.
2.
Density for substance changes based on the size of the piece.
Correct Answer
B. False
Explanation
The density of a substance does not change based on the size of the piece. Density is a physical property of a substance that remains constant regardless of the size or amount of the substance. It is defined as the mass of a substance divided by its volume. Therefore, the density will remain the same regardless of whether the substance is in a large or small piece.
3.
What is the asthenosphere?
Correct Answer
C. Semi-solid magma in the Mantle
Explanation
The asthenosphere is a semi-solid layer in the Earth's mantle. It is located below the lithosphere, which includes the solid crust and uppermost part of the mantle. The asthenosphere is composed of partially molten rock material that is capable of flowing over long periods of time. This layer plays a crucial role in plate tectonics, as it allows the movement of the rigid tectonic plates on top of it.
4.
The Inner Core is thought to be
Correct Answer
A. Solid iron and nickel
Explanation
The inner core is believed to be made up of solid iron and nickel. This is supported by seismic data and the behavior of seismic waves that pass through the Earth's interior. The high pressure and temperature conditions at the center of the Earth are thought to keep the iron and nickel in a solid state, despite their melting points. This solid inner core is believed to be surrounded by a liquid outer core, which is primarily composed of molten iron and nickel.
5.
The mantle is made of
Correct Answer
D. Solid and semi-solid rock
Explanation
The mantle is made of both solid and semi-solid rock. The mantle is the layer of the Earth located between the crust and the core. It is primarily composed of solid rock, but due to the high temperature and pressure, some of the rock in the mantle becomes semi-solid or partially molten. This semi-solid rock is known as the asthenosphere and is responsible for the movement of tectonic plates on the Earth's surface. Therefore, the correct answer is solid and semi-solid rock.
6.
The mass of an object is 30g and the volume is 60cm3. What is the density?
Correct Answer
A. 0.5 g/cm3
Explanation
The density of an object is calculated by dividing its mass by its volume. In this case, the mass of the object is 30g and the volume is 60cm3. Dividing 30g by 60cm3 gives a density of 0.5 g/cm3.
7.
Why does a helium balloon float in the air?
Correct Answer
B. It is less dense than air.
Explanation
A helium balloon floats in the air because it is less dense than the surrounding air. Density is a measure of how much mass is packed into a given volume. When an object is less dense than the fluid it is placed in, it experiences an upward buoyant force that allows it to float. In the case of a helium balloon, the gas inside the balloon is less dense than the air around it, causing the balloon to rise and float in the air.
8.
Oceanic crust is primarily
Correct Answer
C. Basalt
Explanation
Basalt is the correct answer because oceanic crust is primarily composed of this type of rock. Basalt is a dark, fine-grained igneous rock that is formed from solidified lava. It is rich in iron and magnesium, and it is the most common rock type in the oceanic crust. Granite, iron, and marble are not typically found in the composition of oceanic crust.
9.
What happens to temperature as you move from Crust to Core?
Correct Answer
D. Increases
Explanation
As you move from the crust to the core of the Earth, the temperature increases. This is because the core of the Earth is made up of extremely hot molten rock and metal, while the crust is closer to the surface and therefore experiences cooler temperatures. The increase in temperature from the crust to the core is due to the intense heat generated by the Earth's inner layers and the radioactive decay of elements within the core.
10.
What happens to density as you move from Crust to Core?
Correct Answer
C. Increases
Explanation
As you move from the crust to the core of the Earth, the density increases. This is because the core is composed of heavier elements like iron and nickel, while the crust is made up of lighter materials like rocks and minerals. The increased concentration of heavy elements in the core leads to a higher overall density compared to the crust.