LT 2.3 Practice Quiz

What is the primary composition of Earth's inner core?

• Solid iron and nickel

• Liquid iron and sulfur

• Solid silicate rocks

• Liquid water

Answer explanation

The Earth's inner core is primarily composed of solid iron and nickel, which are under immense pressure and temperature, making them solid despite the high temperatures. This distinguishes it from the outer core, which is liquid.

Tags

NGSS.HS-ESS2-3

Which layer of the Earth is responsible for generating most of the planet's magnetic field?

• Crust

• Inner core

• Outer core

• Mantle

Answer explanation

The outer core, composed of liquid iron and nickel, generates the Earth's magnetic field through the movement of these conductive materials, a process known as the geodynamo. The inner core, crust, and mantle do not contribute significantly to this field.

What is the main source of geothermal energy within the Earth?

• Solar radiation

• Radioactive decay

• Ocean currents

• Wind energy

Answer explanation

The main source of geothermal energy within the Earth is radioactive decay. This process generates heat as unstable isotopes break down, contributing significantly to the Earth's internal heat.

Tags

NGSS.HS-ESS2-3

Which process in the Earth's core is primarily responsible for the movement of molten iron?

• Conduction

• Convection

• Radiation

• Sublimation

Answer explanation

Convection is the process responsible for the movement of molten iron in the Earth's core. It involves the transfer of heat through the movement of fluids, causing the molten iron to circulate and create convection currents.

Tags

NGSS.HS-ESS2-3

Which element is NOT a significant contributor to radioactive decay in the Earth's core?

• Uranium

• Thorium

• Potassium

• Carbon

Answer explanation

Carbon is not a significant contributor to radioactive decay in the Earth's core, unlike Uranium, Thorium, and Potassium, which are key isotopes responsible for generating heat through radioactive processes.

Tags

NGSS.HS-PS1-8

What is the state of matter of the Earth's outer core?

• Solid

• Liquid

• Gas

• Plasma

Answer explanation

The Earth's outer core is in a liquid state, primarily composed of molten iron and nickel. This liquid layer surrounds the solid inner core and is responsible for generating the Earth's magnetic field.

Tags

NGSS.HS-ESS2-3

Which of the following best describes the temperature trend as you move from the Earth's crust to its core?

• Decreases

• Remains constant

• Increases

• Fluctuates randomly

Answer explanation

As you move from the Earth's crust to its core, temperature increases due to the intense pressure and heat generated by the Earth's formation and radioactive decay. Thus, the correct answer is 'Increases'.

Tags

NGSS.HS-ESS2-3

Which process is responsible for the generation of heat in the Earth's interior due to unstable atomic nuclei?

• Nuclear fusion

• Radioactive decay

• Photosynthesis

• Evaporation

Answer explanation

Radioactive decay is the process where unstable atomic nuclei break down, releasing energy in the form of heat. This process contributes significantly to the heat generation in the Earth's interior.

Tags

NGSS.HS-PS1-8

What is the main reason the Earth's inner core remains solid despite high temperatures?

• Low pressure

• High pressure

• Lack of radioactive elements

• Presence of water

Answer explanation

The Earth's inner core remains solid despite extreme temperatures due to the high pressure at that depth, which increases the melting point of iron and keeps it in a solid state.

Which of the following is a direct result of convection currents in the Earth's outer core?

• Plate tectonics

• Earth's magnetic field

• Ocean tides

• Volcanic eruptions

Answer explanation

Convection currents in the Earth's outer core generate movement of molten iron, which creates electric currents. These currents produce the Earth's magnetic field, making it the correct answer.

Tags

NGSS.HS-ESS2-3