Convection, process by which heat is transferred by movement of a heated fluid such as air or water . Natural convection results from the tendency of most fluids to expand when heated—i.e., to become less dense and to rise as a result of the increased buoyancy.
How do convection currents flow?
Convection currents form because a heated fluid expands , becoming less dense. The less-dense heated fluid rises away from the heat source. As it rises, it pulls cooler fluid down to replace it. This fluid in turn is heated, rises and pulls down more cool fluid.
How does convection cause movement?
Convection currents drive the movement of Earth’s rigid tectonic plates in the planet’s fluid molten mantle . In places where convection currents rise up towards the crust’s surface, tectonic plates move away from each other in a process known as seafloor spreading (Fig. 7.21).
Why do convection currents occur?
Convection currents are the result of differential heating . Lighter (less dense), warm material rises while heavier (more dense) cool material sinks. It is this movement that creates circulation patterns known as convection currents in the atmosphere, in water, and in the mantle of Earth.
What is the effect of convection currents?
Convection currents drive the movement of Earth’s rigid tectonic plates in the planet’s fluid molten mantle . In places where convection currents rise up towards the crust’s surface, tectonic plates move away from each other in a process known as seafloor spreading (Fig. 7.21).
What are three types of convection?
- Natural convection.
- Forced convection.
Why is the convection important?
This flow, called mantle convection, is an important method of heat transport within the Earth. Mantle convection is the driving mechanism for plate tectonics , which is the process ultimately responsible for producing earthquakes, mountain ranges, and volcanos on Earth.
How does convection affects the formation of mountains?
As tectonic plates slowly move away from each other, heat from the mantle’s convection currents makes the crust more plastic and less dense . The less-dense material rises, often forming a mountain or elevated area of the seafloor. ... This rock (basalt) becomes a new part of Earth’s crust.
Why is convection current in the asthenosphere important?
Convection currents generated within the asthenosphere push magma upward through volcanic vents and spreading centres to create new crust . ... According to the theory of plate tectonics, the asthenosphere is the repository for older and denser parts of the lithosphere that are dragged downward in subduction zones.
Does air move in a convection current?
Convection currents are part of what drives global circulation of the Earth’s atmosphere. ... Convection currents in the air and sea lead to weather . Magma in the Earth’s mantle moves in convection currents. The hot core heats the material above it, causing it to rise toward the crust, where it cools.
What are 5 examples of convection current?
- Breeze. The formation of sea and land breeze form the classic examples of convection. ...
- Boiling Water. Convection comes into play while boiling water. ...
- Blood Circulation in Warm-Blooded Mammals. ...
- Air-Conditioner. ...
- Radiator. ...
- Refrigerator. ...
- Hot Air Popper. ...
- Hot Air Balloon.
Which is the best example of convection current?
Convection currents are present in the air– A good example of convection current is the warm air that rises towards the ceiling in your house . The process happens as the warm air is said to be less dense than that of the colder air. Another good example of convection current is wind.
What are the two types of convection?
There are two types of convection: natural convection and forced convection .
What is convection in simple words?
1 : the action or process of conveying . 2a : movement in a gas or liquid in which the warmer parts move up and the cooler parts move down convection currents. b : the transfer of heat by convection foods cooked by convection — compare conduction, radiation.
