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    This module and collection are included inLens: Siyavula: Natural Sciences (Gr. 7-9)
    By: Siyavula

    Module Review Status: In Review
    Collection Review Status: In Review

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NATUURWETENSKAPPE

Graad 8

ENERGIE: ELEKTRISITEIT, ENERGIE, WARMTE EN LIG

Module 11

LIG

  • Nog ‘n baie bekende energiesoort is LIG.
  • Jou ouers of onderwysers sal baie graag “oë agter hulle koppe wou hê” of vir jou wou sê hulle sien alles. Ons almal weet egter dat dit om ‘n baie eenvoudige rede nie moontlik is nie:

Aktiwiteit 1:

Om ligterme en -begrippe vas te stel

[LU 2.1, 2.3, 2.4]

Lig beweeg in ‘n reguit lyn

Lig kan wel rigting verander en dit gebeur op twee maniere:

  • Ligbreking of REFRAKSIE
  • Weerkaatsing

WEERKAATSING (Soos in die geval van spieëls.)

Wanneer lig teen ‘n sekere hoek inval, sal dit teen dieselfde hoek weerkaats.

INVALSHOEK = WEERKAATSINGSHOEK

Figure 1
Figure 1 (graphics1.png)

Aktiwiteit 2:

Om weerkaatsingbegrippe te vestig

[LU 2.4]

Opdrag 1:

1. Maak nou jou eie spieëlskets met invalshoek en weerkaatsingshoek. Gebruik ‘n gradeboog.

Spieëls wat gerond is, het baie toepassings. Dit vergroot en verander die vorm van beelde. ‘n Spieël kan holrond of KONKAAF wees.

Figure 2
Figure 2 (graphics2.png)

Dit sal strale KONVERGEER (saamtrek) na ‘n vaste punt wat ons die FOKUS noem. Ander spieëls is weer bolrond of KONVEKS. Dit sal strale laat DIVERGEER (uiteenloop) en beelde verklein. Toepassings hiervan is motors se truspieëltjies, asook vleuelspieëls.

Figure 3
Figure 3 (graphics3.png)

Presies dieselfde effek word verkry met gepoleerde metale.

Opdrag 2:

1. Probeer gerus die volgende:

Neem ‘n groot eetlepel en vryf die oppervlak blink.

Vergelyk die verskil in beeld as die konkawe kant en dan weer die konvekse kant na jou toe wys.

Teken die verskil in die spasie voorsien:

Table 1
graphics4.png graphics5.png

Teken konvergerende en divergerende strale van regs af in op die volgende sketse. Vra jou onderwyser om te help.

Figure 4
Figure 4 (graphics6.png)
Figure 5
Figure 5 (graphics7.png)

Assessering

LU 1

Wetenskaplike OndersoekDie leerder is in staat om met selfvertroue op weetgierigheid oor natuurlike verskynsels te reageer, en om binne die konteks van wetenskap, tegnologie en die omgewing verbande te ondersoek en probleme op te los.

Dit word bewys as die leerder:

1.1 ondersoeke kan beplan;

1.2 ondersoeke kan uitvoer en data kan insamel;

1.3 data kan evalueer en bevindinge kan kommunikeer.

LU 2

Wetenskaplike KennisDie leerder ken, interpreteer en pas wetenskaplike, tegnologiese en omgewingskennis toe.

Dit word bewys as die leerder:

2.1 sinvolle inligting kan oproep;

2.2 inligting in kategorieë kan plaas;

2.3 inligting kan interpreteer;

2.4 kennis kan toepas.

LU 3

Wetenskap, Omgewing en die GemeenskapDie leerder is in staat om begrip van die onderlinge verband tussen wetenskap en tegnologie, die samelewing en die omgewing te toon.

Dit word bewys as die leerder:

3.1 wetenskap as ‘n menslike aktiwiteit kan verstaan;

3.2 volhoubare gebruik van die aarde se hulpbronne verstaan.

Memorandum

OPDRAG 1:

LIG

  • Nog ‘n baie bekende soort energie is LIG.
  • Grootmense sou baie graag “oë agter hulle koppe wou hë”, of wou sê hulle sien alles. Ons almal weet egter dat dit nie moontlik is nie, vir ‘n baie eenvoudige rede:
  • Lig beweeg in ‘n reguit lyn, maar lig kan wel rigting verander en dit gebeur op twee maniere: Weerkaatsing enLigbreking of REFRAKSIE

WEERKAATSING:

  • Soos in die geval van spieëls.

Wanneer lig teen ‘n sekere hoek inval sal dit teen dieselfde hoek weerkaats.

INVALSHOEK = WEERKAATSINGSHOEK

Figure 6
Figure 6 (graphics8.png)

GERONDE SPIEËLS

  • Spieëls wat gerond is, het baie toepassings.
  • Dit vergroot en verander die vorm van ‘n beeld.
  • ‘n Spieël kan holrond of KONKAAF wees.

Figure 7
Figure 7 (graphics9.png)
  • Dit sal strale KONVERGEER (saamtrek) na ‘n vaste punt wat ons die FOKUS noem.
  • Ander spieëls is weer bolrond of KONVEKS.
  • Dit sal strale laat DIVERGEER (uiteenloop)
  • Dit verklein die beeld.
  • Toepassings hiervan is motors se truspieëltjies, asook vleuelspieëls.
Figure 8
Figure 8 (graphics10.png)
  • Probeer gerus die volgende:
  • Neem ‘n groot eetlepel en vryf die oppervlak blink.
  • Vergelyk die verskil in beeld as die konkawe kant en dan weer die konvekse kant na jou toe wys.

Teken die verskil in die spasie voorsien

Table 2
graphics11.png graphics12.png

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Definition of a lens

Lenses

A lens is a custom view of the content in the repository. You can think of it as a fancy kind of list that will let you see content through the eyes of organizations and people you trust.

What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

Who can create a lens?

Any individual member, a community, or a respected organization.

What are tags? tag icon

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

| External bookmarks