Grade 7: Methods of Heat Transfer

• Science
• Primary Education
• Age 13

Grade 7 Science: Methods of Heat Transfer

Heat Transfer

Conduction and Convection currents

How does conduction occur?

1. By fluid motion
2. Through direct contact between particles
3. By pressure waves
4. By electromagnetic waves

What causes conduction?

1. Movement of charged particles
2. Transfer of heat through radiation
3. Transfer of heat through convection and radiation
4. Transfer of heat through convection

Human activities can influence convection currents and impact global climate.

Certainly, evidence shows human-induced changes.

Partly, but nature has a greater impact.

Not significantly, natural processes are dominant.

Undecided, more studies are necessary for confirmation.

Convection currents are the main cause of weather patterns.

Definitely true, scientific evidence supports it.

Partially true, but other factors contribute too.

Not true, there are alternative explanations.

Unsure, more research is needed to confirm.

Convection Currents

The movement of faster moving particles up and slower moving particles. 

What happens to particles when they are heated?

1. Descend and become more dense
2. Rise and become less dense
3. Rise due to becoming more dense
4. Descend and become less dense

What do you think of when you hear the word conduction?

What property makes a material a good conductor?

1. Opaque to light
2. Low melting point
3. High electrical conductivity
4. Strong magnetic field

What is a conductor?

1. A type of musical instrument.
2. A material that allows the flow of electric current.
3. A material that prevents the flow of electric current.
4. A person who directs an orchestra.

What do you think when you hear the word convection?

What are some real life examples of convection current.

What is an example of a convection current?

1. Hand feeling hot when touching a spoon
2. Top of the la

Heat causes the particles to move faster and become less dense. 

What happens to particles when they are cooled?

1. becomes denser and rises
2. Become less dense and descend
3. Become more dense and ascend
4. Become less dense and descend

What are convection currents?

It is when particles from liquids or gases move in a circular motion with particles with higher kinetic energy rising and lower kinetic energy descending. 

What does it mean to have higher kinetic energy?

Drag and Drop activity

Your hand feels cold when you touch a piece of ice. 

Your hand feels very hot as you put the spoon into the boiling water. 

You get colder as you swim towards the bottom of the lake. 

Convection current

Conduction

https://www.greatschools.org/library/cms/02/25802.pdf

Text

What are some real life examples of convection currents?

How confident do you feel about your knowledge of convection currents and conduction?

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Can you think of some other real life examples of convection currents and conduction?

Hint

Think about how your house is heated or how water is boiled. 

What are real life examples of convection currents?

Examples of Conductors

Conduction

• Thermal energy is transferred from the fast moving particles to the slower moving particles. Heat is transferred from areas of higher thermal energy to those of lower thermal energy. 
  

Particle Theory of Matter

Heating a room

Heating a kettle

How confident do you feel about your knowledge of convection currents?

😒🙁😐🙂😃

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