View
214
Download
1
Category
Preview:
Citation preview
Reflection & Mirrors
Recap:Diffuse reflection: gives a blurry image (or none at all)
Specular reflection: gives a clear image
Mirror types:PLANE CONVEX CONCAVE
Plane Mirrors• The image formed by plane
mirrors can only be seen behind the mirror.
• This is known as a virtual image.
• Image is the same size as the object.
• Only the right and left of the image is changed.
Curved Mirrors• Curved mirrors can be either– concave (making a little cave) – Causes light to converge
– convex (vexing out in the middle) – Causes light to diverge
Law of Reflection
Ray Diagrams
• Show path of light from object mirror away from mirror
• Allows you to determine the location and properties of an image formed by a mirror or lens
Ray Diagram: Basic set-up
** r = 2f
mirror
Principal axisC
(center of curvature)
F(focal point)
f(focal length)
r(radius of curvature)
Ray Diagrams: images
• REAL vs. VIRTUAL• UPRIGHT vs. INVERTED• SAME SIZE, SMALLER, ENLARGED
COMPARE IMAGE TO ORIGINAL OBJECT
Real or Virtual
Real images can project on a screen
Virtual images can only be seen in a mirror
Upright or Inverted
Upright images are oriented the same as the object
Inverted images are oriented in the opposite direction as the object
Reduced or Enlarged
Reduced images are smaller in size than the object
Enlarged images are larger in size than the object
Get ready to draw diagrams…
• Take 2 different colored pencils• Take a slice of index card/Ruler– This will be your straight-edge– PUT YOUR NAME ON IT & KEEP IT– Decorate it if you want to
• Take a notes packet
• Ready? Let’s do this!
Concave Mirror A
F
Step 1: draw horizontal ray from top of object to mirrorStep 2: draw reflected ray from point where ray hits mirror through focal pointStep 3: draw second ray from top of object through focal point to mirrorStep 4: draw reflected ray from point where ray hits mirror horizontally backStep 5: draw image from principal axis to intersection of reflected rays
Image is:REALINVERTEDLARGERFARTHER
Concave Mirror B
F
Step 1: draw horizontal ray from top of object to mirror Step 2: draw reflected ray through focal point Step 3: draw second ray from focal point, through top of object, to mirror Step 4: draw horizontal reflected ray Step 5: continue both reflected rays behind mirror as DASHED LINES Step 6: draw image from principal axis to intersection of reflected rays
Image is:VIRTUALUPRIGHTLARGERFARTHER
Convex Mirror
F
Step 1: draw horizontal ray from top of object to mirror Step 2: draw reflected ray from focal point through point where ray hit mirror and out Step 3: draw angled ray, aimed at focal point, to mirror Step 4: draw horizontal reflected rayStep 5: continue both reflected rays behind mirror as DASHED LINES Step 6: draw image from principal axis to intersection of reflected rays
Image is:VIRTUALUPRIGHTSMALLERCLOSER
• Questions?
• Begin optics packet!
Recommended