Lesson 10

• Physics
• Middelbare school
• vwo
• Leerjaar 3

Chapter 3 Energy — Section  2 & 3

This lesson

• Specific heat capacity calculations
• Insulation
• Heat transfer
• Discussing the homework

Learning goals

At the end of this lesson you can:

• Rearrange the formula for specific heat
• Explain how double glass works
• Name the three forms of heat transfer and examples for each
• Do calculations on quality of insulation

Specific heat capacity

Q=c⋅m⋅ΔT

The amount of thermal energy required to heat 1 gram of a substance 1 ºC.

How easily a substance heats up.

Q: Heat in joules (J)

c: The specific heat capacity of a s substance (J/(g•ºC)

m: The mass of a substance in grams (g)

ΔT = T end - T start : The temperature difference (ºC)

Section 3 — Inulsation

Understanding double glass

Heat transfer

Three forms of heat transfer:

• Conduction
  
• Convection
  
• Radiation
  

Exercise — Heat transfer

Three forms of heat transfer:

• Conduction
  
• Convection
  
• Radiation
  

Come up with three examples of for each form of heat transfer

Exercise — Heat transfer

Three forms of heat transfer:

• Conduction
  
• Convection
  
• Radiation
  

Come up with three examples of for each form of heat transfer

Conduction

• A radiator
  
• Holding a hot cup of tea
  
• A pan on a stove
  

Convection

• Warm water flowing through a tap
  
• A cold breeze in the summer
  
• Steam coming of boiling water
  

Radiation

• A campfire
• The sun
• Electric heating

Quality of insulation

Q: Heat in joules (J)

U: the quality of insulation of the wall (W/m²•ºC)

A: The surface area of the wall (m²)

ΔT = T end  - T start : The temperature difference (ºC)

Q=U⋅A⋅ΔT

The property of a material of it's quality of insulation

Discussing the homework

Section 3

Exercise 1, 2, 4, 5, 6

Exercise 8, 9

Section 4

• Chapter 3, section 3 exercise 8 and 9
• Read chapter 3, section 4
• Do exercise 1, 2, 3 and 

Learning goals

At the end of this lesson you can:

• Rearrange the formula for specific heat
• Explain how double glass works
• Name the three forms of heat transfer and examples for each
• Do calculations on quality of insulation