2-7 efficiency (4.4)

Efficiency (4.4) 
Stationary
- Writingbook, iPad
- Pen, pencil, geotriangle
- Calculator


Schoolbags in
the cupboard
Phones in the phone bag
Bluetooth 
- ON
- VPN off
1 / 16
next
Slide 1: Slide
NatuurkundeMiddelbare schoolhavoLeerjaar 3

This lesson contains 16 slides, with interactive quizzes and text slides.

time-iconLesson duration is: 50 min

Items in this lesson

Efficiency (4.4) 
Stationary
- Writingbook, iPad
- Pen, pencil, geotriangle
- Calculator


Schoolbags in
the cupboard
Phones in the phone bag
Bluetooth 
- ON
- VPN off

Slide 1 - Slide

Lesson goals:
  • Explain what efficiency is.
  • Explain how you can make your energy usage sustainable.
  • Calculate efficiency with the following equations:


  • Calculate the efficiency of a boiler.


Enut=Q=cmΔT

Slide 2 - Slide

Sustainable energy usage
Efficiency indicates whichpotion of the available energy is usefully consumed.

Slide 3 - Slide

Calculating efficiency

Slide 4 - Slide







blz 158

Slide 5 - Slide

3,8 J of 6,5 J energy is converted into light in a lightbulb. What is the efficiency of the lightbulb?
A
171%
B
58%
C
37%
D
15%

Slide 6 - Quiz

Efficiency of a boiler
Etot = Calculate the ammount of heat: 
                     volume x calorific value
The calorific value of methane gas (natural gas) is 32 MJ/m3

Eusefull = Q =
cmΔT

Slide 7 - Slide

Euseful in a boiler



c = specific heat of water
m = mass (of water)
      = change in T in 0C
Eusefull=Q=cmΔT
ΔT

Slide 8 - Slide

Slide 9 - Slide

Slide 10 - Slide

Slide 11 - Slide

Slide 12 - Slide

What is the energy used if 16 liter of water increases temperature from 13 to 98 degrees Celsius. Show all your calculations.

Slide 13 - Open question

Bereken de hoeveelheid warmte van 0,35 m3 aardgas. Vul alleen je antwoord zonder eenheid in. gebruik een , en niet een .

Slide 14 - Open question

Calculate the heat released by 0,35 m3 natural gas. Show your calculations.

Slide 15 - Open question

                        Now make the test yourself paragraph 4.4
     and then question 40, 41 and 44

Slide 16 - Slide