2-2 Transporting electrical energy (2.1)

• Natuurkunde
• Middelbare school
• havo
• Leerjaar 3

Transporting electrical 

energy (p. 54)

Stationary

- Writingbook, iPad

- Pen, pencil geotriangle

- Calculator

Schoolbags in

the cupboard

Phones in the phone bag

Bluetooth 

- ON

- VPN off

Lesson goals:

• Expain what voltage is needed at different points in the electrical grid.

• Explain how a transformer works.
  
• Calcualte the voltage or the number of windings

        in a coil of a transformer.

Electrical grid:

• If a current moves through a conductor, it becomes warm.

          Energy loss: less energy is left for the user 

• To minimize the energyloss the current must be transported at the highest possible voltage (less heat).

Powerstation

Transformer

380kV

10kV

230 V

Types of current

• The electrical grid does not use direct current (like batteries do) but alternating current (with goes to and fro 50 times per second, the frequency is 50 Hz)

Why do we increase the current when electricity is transported over long distances?

1. For safety
2. To minimise energy loss
3. To establish a frequency of 50 Hz
4. Because this is the voltage devices need

What is the voltage in our houses?

1. 20 kV
2. 380 kV
3. 10 kV
4. 230 V

The working of a transformer

How are the coils connected?

1. Magnetic
2. Electric

Formula

​U​s​​​​U​p​​​​​​​=​N​s​​​​N​p​​​​

      = voltge primary coil (V)

      = Voltage secondary coil (V)

      = number of windings

          in the primary coil

      = number of windings

          in the secondary coil

U​p​​

U​s​​

N​p​​

N​s​​

             MAAK DE VOLGENDE OPGAVE

            1 t/m 4 (blz 59) en 6, 8 (blz 60)

ALS JE KLAAR BENT: 

REGELS:

• Schrijven in je schrift
  



• Hulp: je boek
• Geen overleg (wel muziekje)
  


• Over 15 minuten bespreken we de opgaven
  

Voor extra oefening maak ook opgaven 9

Lesafsluiting

Elektrische energie wordt opgewekt:

Brander, turbine, generator, condensor

Elektrische energie wordt vervoert naar onze huizen:

380 kV, 10 kV, 230 V

Werking van een transformator

​U​s​​​​U​p​​​​​​​=​N​s​​​​N​p​​​​

Hoeveel van de inhoud van de les van vandaag begrijp je?

1. niks
2. beetje
3. de meeste
4. alles