Heat transfers on Earth

How is Heat Transferred?

• The movement of energy from a warmer object to a cooler object is called heat transfer.

• There are 3 types of heat transfer:

• Radiation

• Conduction

• Convection

Radiation

• The transfer of energy that is carried in rays like light

• Ex: the Sun transfers heat and light through the air, warming your skin

Multiple Select

What are 2 sources of Radiation other than dangerous metals?

• Sun

• Fire

• Ocean currents

• Air currents

• Mantle

Conduction

• Heat transfer between materials that are touching

• Ex: Grabbing a hot pan transfers heat to your hand

Multiple Choice

Which one carries the radiation energy

• Air

• Human

• Sunlight

• water

Convection

• Heat transfer by the movement of a fluid (liquid or gas)

• Ex: Eagles can glide on warm air currents produced by rising heat from the ground

Differential Heating

Which heats up and cools down more slowly – water or land?

Multiple Choice

What is the definition of CONDUCTION?

• When heat is transferred from objects like rays of light or electromagnetically.

• a hot liquid or air that expands, becomes less dense, and rises or becomes more dense, and sinks.

• When heat transfers from objects that are touching.

• When heat transfers through the heater or AC in your house.

Convection Currents

• Density - a measure of how much mass there is in a given volume

• Convection Current - the flow that transfers heat within a fluid

• Convection currents work by warmer, less dense, fluid rising and colder, more dense, fluid sinking

Multiple Choice

Near the ceiling of a room the air is warmer. The warm air rises because of ________.

• conduction

• convection

• radiation

Convection Currents

• ***These 3 things set convection currents in motion***

• Heating and cooling of a fluid

• Changes in the fluid's density

• The force of gravity

Multiple Choice

In heat transfer, heat always flows from the _______________ substance to the _______________ substance.

• hotter to colder

• colder to hotter

• hotter to hotter

• colder to colder

Convection Currents in Earth

• Heat from the core and the mantle itself cause convection currents inside the mantel

• The middle portion of the mantel, the asthenosphere, is plastic-like due to this heat

• As lower parts of the asthenosphere are heated, they become less dense and begin to rise

• When this section reaches the top, it spreads out, cools off, and begins to sink back to the bottom

Multiple Choice

How is heat transferred when boiling a pot of water on the stove?

• conduction

• convection

• combustion

• radiation

Multiple Choice

Land heats up and cools down faster than water.

• True

• False

Convection Currents in Earth continued...

• When the section of asthenosphere reaches the top it transfers heat to the lithosphere through conduction

• Convection currents also occur inside the outer core

• The outer core is mostly liquid iron and nickel

• These currents cause Earth's magnetic fields

Multiple Choice

Which best describes the process of convection?

• Convection is the primary way heat travels through rays.

• Convection is the primary way heat travels through metals.

• Convection is the primary way heat travels through appliances.

• Convection is the primary way heat travels through liquids and gasses.

Differential Heating

This is called differential heating. This is what moderates the climate in coastal areas.

In winter, the ocean acts like a giant heater and in summer, the ocean acts like a giant air conditioner.

Multiple Choice

Which is an example of heat being transferred by conduction?

• a furnace blowing hot air through vents

• an ice cube melting in a person’s hand

• boiling water transferring heat to noodles

• the sun heating water in a swimming pool

Multiple Choice

Which direction will the heat flow while this person holds a hot cup of tea?

• from the cup to her hand

• from her hand to the cup

• no heat is transferred

Multiple Choice

Which best describes the process of convection?

• Convection is the primary way  heat travels  through rays.

• Convection is the primary way heat travels  through metals.

• Convection is the primary way heat travels  through appliances.

• Convection is the primary way heat travels  through liquids and gasses.