Year 11 Physics Waves Rays Model of light – (B) Experiment using Lenses

HOW TO WRITE INQUIRY QUESTION AND DRAW RAY DIAGRAMS FOR EXPERIMENTS USING LENSES?

Syllabus DOT POINT:

3.4a. Conduct a practical investigation to analyse the formation of images in mirrors and lenses via reflection and refraction using the ray model of light (ACSPH075)  

EXPERIMENT (A) Physics Practical Investigation: (B) Refraction of rays through convex and concave lenses.

AIM: To analyse the formation of reflected images from convex and concave lenses.

INQUIRY QUESTION: Link inquiry question to the aim of the experiment and write a hypothesis in the form of a question.  Examples of inquiry question are as given below.

  • What are the properties of reflected images formed from convex and concave lenses and how are these images formed? 
  • How are the reflected images in convex and concave lenses formed and what are the properties of these images?
  • How to use ray diagrams to determine the properties of images formed from convex and concave lenses?

What are the characteristics or properties of the reflected image? It is helpful to use SLOT – where:

S – represents the size of the image (same size, magnified or diminished (smaller) compared to the object.

L – represents the location of the image (how far is it from the mirror).

O- represents the orientation of the image (upright or inverted)

T- represents the type of the image (real or virtual). Real images refer to images formed on the same size as the object and can be captured on a screen. Virtual images are formed on the opposite side of the object.

(i) size of the image compared to the actual object (same size or magnified (larger) or diminished (smaller)

(ii) upright

(iii) laterally inverted (left-right reversed)

(iv)real (means the image is formed on the same size of the mirror as the object and can be observed by placing a screen

or virtual  (means the image is formed on the opposite side of the mirror as the object and like see your image behind the mirror).

 

HOW TO DRAW RAY DIAGRAMS CORRECTLY IN A SCIENTIFIC INVESTIGATION?

A – Experiment Using Lenses  – Drawing Ray diagrams and description of image

1.1 Convex Lens

Ray diagrams -Poorly drawn Ray diagrams – correctly drawn Description of image

Characteristics or properties of the image)

Common Mistakes:

  • No arrow (direction) on the refracted ray  
  • The Focal point  not labelled
Comments:

  • Arrow (direction) indicated on refracted ray
  • The Focal point ls correctly labelled
Refer to ray diagram

 

1.2 Concave lens  

 

Ray diagrams -Poorly drawn Ray diagrams – correctly drawn Description of image

Characteristics or properties of the image)

Common Mistakes:

  • Using dotted lines to draw reflected rays.
  • No arrows (direction) on reflected rays
  • Focal point not indicated.
  • Inaccurate drawings of reflected rays leading to inaccurate location of  focal point.
Comments:

  • Arrow (direction) indicated on reflected ray.
  • Correct label for virtual focal point, y.
  • Accurate drawings of reflected rays. Leading to accurate location of focal point.
(i) If the object is placed further than the focal point, the image is:

  • real   
  • magnified if it is more than twice the focal length OR  smaller if between focal length and less than twice the focal length.
  • laterally inverted(left-right reversed)
  • inverted

(ii) If the object is placed closer than the focal  length, the image

  • virtual  
  • Magnified (larger than the original object).  
  • laterally inverted(left-right reversed)
  • inverted

(iii) If the object is placed at the focal  length,

  • virtual  
  • Magnified (larger than the original object).  
  • laterally inverted(left-right reversed)
  • inverted

 

 

 

 

 

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Year 11 Physics Waves and Thermodynamics – Rays Model of light – (A) Experiment using Mirrors

HOW TO WRITE INQUIRY QUESTION AND DRAW RAY DIAGRAMS FOR EXPERIMENTS USING MIRRORS?

Syllabus DOT POINT:

3.4a. Conduct a practical investigation to analyse the formation of images in mirrors and lenses via reflection and refraction using the ray model of light (ACSPH075)  

EXPERIMENT (A) Physics Practical Investigation: (A) Wave Depth Studies Reflection and formation of images in plane, convex and concave mirrors. 

AIM: To analyse the formation of reflected images in mirrors.

INQUIRY QUESTION: Link inquiry question to the aim of the experiment and write a hypothesis in the form of a question as shown in the examples below.

  • What are the properties of reflected images in convex, concave and plane mirrors and how are these images formed? (corrected)
  • How are the reflected images in convex, concave and plane mirrors formed using ray diagrams what are the properties of these mages?

What are the characteristics or properties of the reflected image? It is helpful to use SLOT – where:

S – represents the size of the image (same size, magnified or diminished (smaller) compared to the object.

L – represents the location of the image (how far is it from the mirror).

O- represents the orientation of the image (upright or inverted)

T- represents the type of the image (real  or virtual). Real images refers to images formed on the same size as the object and can be captured on a screen. Virtual images are formed on the opposite side of the object.

(i) size of the image compared to the actual object (same size or magnified (larger) or diminished (smaller)

(ii) upright

(iii) laterally inverted (left-right reversed)

(iv)real (means the image is formed on the same size of the mirror as the object and can be observed by placing a screen

or virtual  (means the image is formed on the opposite side of the mirror as the object and like see your image behind the mirror).

 

HOW TO DRAW RAY DIAGRAMS CORRECTLY IN A SCIENTIFIC INVESTIGATION?

A – Experiment Using Mirrors  – Drawing Ray diagrams and description of image

1.1 Plane mirror

Ray diagrams -Poorly drawn Ray diagrams – correctly drawn Description of image

Characteristics or properties of the image)

Incorrect ray diagram for plane mirror

Common Mistakes:

  • No arrow (direction) on the reflected ray  
  • Normal drawn but (not labelled)
  • Incorrect labels for angle i and angle r

Correct ray diagram for plane mirror

Comments:

  • Arrow (direction) indicated on reflected ray
  • Normal drawn and labelled
  • Correct label for angle i and angle r.
Image is:

  • Virtual
  • Upright
  • Laterally inverted (left-right reversed)
  • Same distance behind the mirror as the object is in front of the mirror.
  • same size as the object.

 

1.2 Concave mirrors  

 

Ray diagrams -Poorly drawn Ray diagrams – correctly drawn Description of image

Characteristics or properties of the image)

Common Mistakes:

  • Using dotted lines to draw reflected rays.
  • No arrows (direction) on reflected rays
  • Focal point not indicated.
  • Inaccurate drawings of reflected rays leading to inaccurate location of  focal point.
Comments:

  • Arrow (direction) indicated on reflected ray.
  • Correct label for virtual focal point, y.
  • Accurate drawings of reflected rays. Leading to accurate location of focal point.
(i) If the object is placed further than the focal point, the image is:

  • real   
  • magnified if it is more than twice the focal length OR  smaller if between focal length and less than twice the focal length.
  • laterally inverted(left-right reversed)
  • inverted

(ii) If the object is placed closer than the focal  length, the image

  • virtual  
  • Magnified (larger than the original object).  
  • laterally inverted(left-right reversed)
  • inverted

(iii) If the object is placed at the focal  length,

  • virtual  
  • Magnified (larger than the original object).  
  • laterally inverted(left-right reversed)
  • inverted

 

1.3 Convex mirrors

Ray diagrams -Poorly drawn Ray diagrams – correctly drawn Description of image

Characteristics or properties of the image)

Common Mistakes

  • Using solid lines to extrapolate reflected rays behind the mirror.
  • No arrows (direction) on reflected rays
  • Focal point not indicated.

Comments:

  • Using dotted lines to extrapolate                 reflected rays behind the mirror.
  • Correct label for virtual focal point, y.
  • Accurate drawings of reflected rays. Leading to accurate location of focal point.
Image is:

  • Virtual
  • Upright
  • Laterally inverted (left-right reversed)
  • Diminished (smaller than  the object).