Chapter 5 Plate Tectonics Section 2 Convection and the Mantle
Het transfer by radiation take place with no direct contact between a heat source and an object.
Sunlight is radiation that warms Earth's surface. Other familiar forms of radiation include the hear you feel around a flame or open fire.
What causes convection currents in the mantle?
heat from the core and the mantle itself causes convecton currents in the mantle.
The movement of energy from a warmer object to a cooler object is called
heat transfer.
Convection
is heat transfer by the movement of currents within a fluid.
Name two layers of Earth in which convection currents take place.
mantle and outer core
In conduction the heated particles of a substance transfer heat through contact with other particles in the substance. Conduction heats the spoon and the pot itself. That is why you need a mitt to protect your hand from the hot handle.
Conduction example
Describe how convection currents form.
Convection Currents forms by the heating and cooling of the fluid, changes in the fluid's density, and the force of gravity combine to set the convection currents in motion
Convection Currents
Differences in temperature and density cause convection currents. In the pot, convection currents arise because the soup close to the heat source is hotter and less dense thant the soup near the surface.
What causes convection currents in Earth's mantle?
Heat from the core and the mantle itself causes convection currents in the mantle
How is heat transferred through space?
Heat is transferred through space by radiation.
What causes heat tranfer by convection?
Heat transfer by convection is caused by differenes of temperature and density within a fluid.
Conduction
Heat transfer within amaterial or between materials that are touching is called ___________________.
What causes convection currents?
Heating and cooling of the fluid, changes in the fluid's density, and the force of gravity combine to set convection currents in motion
What causes convection currents?
Heating and cooling of the fluid, changes in the fluid's density, and the force of gravity combine to set convection currents in motion.
What happens to the density of a fluid as it becomes hotter?
It becomes less dense because the particles are spreading out.
How is it possible for mantle rock to flow?
Over millions of years, the great heat and pressure in the mantle cause solid mantle rock to flow very slowly.
What is the role of gravity in creating convection currents?
The role of gravity is the force pushing it.
Radiation
The transfer of energy through space is called______________.
In the Earth's mantle, large amounts of hear are transferred by convection currents.
True/False (true)
What makes an object hot?
When an object is heated, the particles that make up the object mover faster. The faster-moving particles have more energy.
How is heat transfered?
always from a warmer substance to a cooler substance. There are 3 ways: RADIATION, CONDUCTION, CONVECTION
During convection,
heated particles of fluid begin to flow. This flow transfers heat from one part of the fluid to another.
Density
is a measure of how much mass there is in a volume of a substance.
Earth's molten outer core
is nearly as hot as the surface of the sun.
Convection currents
is the flow that transfers heat within a fluid.
What happens when a fluid cools?
its particles move more slowly and settle together more closely. As the fluid becomes cooler, its density increases.
What is a convection current?
the flow that transfers heat within a fluid
What happens when a liquid or gas is heated?
they move faster and spread apart, take up more space, and the fluid's density decreases
What cause convection currents in the mantle?
• Heat from the core and the mantle itself causes convection currents in the mantle
What will happen to the convection currents in the mantle if Earth's interior eventually cools down? Explain
>They will stop because they are caused because of heat, but if there is no heat, the currents would stop., > If the convection currents eventually cool down then it will continue to cool down unless it got heat added to it. This would cause the magnetic field to stop.
There are also convection currents in the outer core.
These convection currents cause Earth's magnetic field.
Heat always moves from a warmer substance to a cooler substance.
True/false (true)
What are the three types of heat transfer?
radiation, conduction, and convection