Ch18.1 Mirrors Concave mirror All light rays that come in parallel to the optical axis, reflect thru the focal point. All light rays that come in thru

Ch18.1 MirrorsConcave mirror All light rays that come in parallel to the optical axis,

reflect thru the focal point. All light rays that come in thru the focal point, reflect out parallel. the Law of Reflection is always obeyed.

Ch18.1 MirrorsConcave mirror All light rays that come in parallel to the optical axis,

reflect thru the focal point. All light rays that come in thru the focal point, reflect out parallel. the Law of Reflection is always obeyed.

center of focal optical axis curvature point

The center of curvature (radius of curvature) = twice the focal lengthC = 2f

Equations:Lens/Mirror Equation:

focal object imagelength distance distance

- when di = (+) real image- when di = (–) virtual image

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Equations:Lens/Mirror Equation:

focal object imagelength distance distance

- when di = (+) real image- when di = (–) virtual image

Magnification Eqns:

image height

object height

- when hi is (+) image is upright

- when hi is (–) image is inverted

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Ex1) Find the image of a 2 cm tall object placed 11 cm in front ofa concave mirror with a focal length of 5 cm.


Real, Inverted, smaller

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Real, Inverted, larger

- when object is: do > c then di smallerc > di > f

- when object is: c > do > f then di largerCh18 HW#1 1-4 di > c

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Ch18 HW#1 1 – 4 1) Find the image of a 1 cm tall object placed 10 cm in front ofa concave mirror with a focal length of 6 cm.


Real, Inverted, larger

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Real, inverted,same size

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Real, inverted,same size

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Ch18.1 contEx1) A 1cm tall object is placed 2cm in front of a concave mirror with a focal length of 4cm. Find the image.

Ch18.1 contEx1) A 1cm tall object is placed 2cm in front of a concave mirror with a focal length of 4cm. Find the image.

VirtualUprightLarger

When the object is placed inside the focal lengthof a concave mirror, the image is larger and virtual.

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Ex2) A 0.5cm tall object is placed 2cm in front of a concave mirror with a center of curvature of 6cm. Find the image.

Ex2) A 0.5cm tall object is placed 2cm in front of a concave mirror with a center of curvature of 6cm. Find the image.


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Plane Mirrors- focal length at infinity- always form virtual images- image is same height and distance behind mirror

Ex3) A 2cm tall object is placed 3.5cm in front of a plane mirror. Find the image.

Plane Mirrors- focal length at infinity- always form virtual images- image is same height and distance behind mirror

Ex3) A 2cm tall object is placed 3.5cm in front of a plane mirror. Find the image.

Virt,up,same

Ch18 HW#2cmd

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Ch18 HW#2 5 – 7 5. A 1cm tall object is placed 3cm in front of a concave mirror with a focal length of 5cm. Find the image.

Ch18 HW#2 5 – 7 5. A 1cm tall object is placed 3cm in front of a concave mirror with a focal length of 5cm. Find the image.


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Ch18 HW#2 5 – 7 6. (Scaled 3:1) A 3cm tall object is placed 6cm in front of a concave mirror with a focal length of 18cm. Find the image.

Ch18 HW#2 5 – 7 6. (Scaled 3:1) A 3cm tall object is placed 6cm in front of a concave mirror with a focal length of 18cm. Find the image.


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7. A 2cm tall object is placed 5cm in front of a plane mirror. Find the image.

7. A 2cm tall object is placed 5cm in front of a plane mirror. Find the image.

Virt,up,same

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Ch18.2 Convex Mirrors Ex1) A convex security mirror at ur local minimart catches u takinga 5-finger discount from the twinkies. If the mirror has a radius of curvature of 7m, u r 2 m tall, standing 5m in front of the mirror,find ur image.

Ch18.2 Convex Mirrors Ex1) A convex security mirror at ur local minimart catches u takinga 5-finger discount from the twinkies. If the mirror has a radius of curvature of 7m, u r 2 m tall, standing 5m in front of the mirror,find ur image.

VirtualUprightSmaller

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1.2)2(

Ex2) A 2.5cm object is placed 4cm in front of a convex mirror with a focal length of -3cm. Find the image.

Ex2) A 2.5cm object is placed 4cm in front of a convex mirror with a focal length of -3cm. Find the image.


Ch18 HW#3 8 – 10

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Ch18 HW#3 8 – 108. A 10cm object is placed 20cm in front of a convex mirror with a focal length of -15cm. Find the image. (Scaled 5:1)

Ch18 HW#3 8 – 108. A 10cm object is placed 20cm in front of a convex mirror with a focal length of -15cm. Find the image. (Scaled 5:1)


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9. A 2.5cm object is placed 6cm in front of a convex mirror with a focal length of -2cm. Find the image.



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10. A 2cm object is placed 4cm in front of a convex mirror with a focal length of -4cm. Find the image.

10. A 2cm object is placed 4cm in front of a convex mirror with a focal length of -4cm. Find the image.


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Ch18 Mirror Constructions 1. Find the image of a 2cm tall object placed 7cm in front ofa concave mirror with a focal length of 3 cm.

2. A 1.0cm tall object is placed 1.5cm in front of a concave mirror with a focal length of 3cm. Find the image.

2. A 1.0cm tall object is placed 1.5cm in front of a concave mirror with a focal length of 3cm. Find the image.


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3. A 2cm tall object is placed 4.5cm in front of a plane mirror. Find the image.

3. A 2cm tall object is placed 4.5cm in front of a plane mirror. Find the image.

Virt,up,same

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4. Find the image of a 2cm tall object placed 10cm in front ofa concave mirror with a focal length of 4 cm.

4. Find the image of a 2cm tall object placed 10cm in front ofa concave mirror with a focal length of 4 cm.


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6. Find the image of a 0.2cm light bulb placed 5cm in front ofa concave mirror with a focal length of 5 cm.

6. Find the image of a 0.2cm light bulb placed 5cm in front ofa concave mirror with a focal length of 5 cm.

No image

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Lab18.1 Mirrors

- due tomorrow

Ch18.3 – Convex LensesEx1) Find the image of a 1.5cm tall object placed 8cm in front ofa convex lens with a focal length of 5 cm.

Ch18.3 – Convex LensesEx1) Find the image of a 1.5cm tall object placed 8cm in front ofa convex lens with a focal length of 5 cm.

RealInvertedLarger

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3.13)5.1(

Ex2) Find the image of a 2cm tall object placed 10cm in front ofa convex lens with a focal length of 4 cm.


RealInvertedSmaller

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Virtual, Up, Larger

Ch18 HW#4 11 – 14

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Ch18 HW#4 11 – 14 11. Find the image of a 1cm tall object placed 6cm in front ofa convex lens with a focal length of 4 cm.


Real InvLarger

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12. Find the image of a 2cm tall object placed 10cm in front ofa convex lens with a focal length of 4 cm.

12. Find the image of a 2cm tall object placed 10cm in front ofa convex lens with a focal length of 4 cm.

RealInvertedSmaller

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13) Find the image of a 1cm tall object placed 2cm in front ofa convex lens with a focal length of 4 cm.

13) Find the image of a 1cm tall object placed 2cm in front ofa convex lens with a focal length of 4 cm.

Virtual, Up, Larger

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14) Find the image of a 4cm tall object placed 12cm in front ofa convex lens with a focal length of 20 cm. (Scaled 4:1)

14) Find the image of a 4cm tall object placed 12cm in front ofa convex lens with a focal length of 20 cm. (Scaled 4:1)

Virtual, Up, Larger

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Ch18.4 – Concave LensesEx1) Find the image of a 2cm tall object placed 6cm in front ofa concave lens with a focal length of –4 cm.

Ch18.4 – Concave LensesEx1) Find the image of a 2cm tall object placed 6cm in front ofa concave lens with a focal length of –4 cm.

Virtual, Up, Smaller

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Eye Problems

Normal Eye focuses light on the retina:

Eye Problems

Farsighted – rays meets behind the retina:

Fix with:

Eye Problems

Nearsighted – rays meets in front of the retina:

Fix with:

Ch18 HW#5 15 – 18



No image

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16. Find the image of a 2.5cm tall object placed 6cm in front ofa concave lens with a focal length of –4 cm.

16. Find the image of a 2.5cm tall object placed 6cm in front ofa concave lens with a focal length of –4 cm.


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17. Find the image of a 25cm tall object placed 40cm in front ofa concave lens with a focal length of –30 cm.

17. Find the image of a 25cm tall object placed 40cm in front ofa concave lens with a focal length of –30 cm.


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Eye Problems

Nearsighted fix with _________ lens:

Eye Problems

Nearsighted fix with concave lens:

Ch18 Lens Constructions1. Find the image of a 1.5cm tall object placed 9cm in front ofa convex lens with a focal length of 3cm.

Ch18 Lens Constructions1. Find the image of a 1.5cm tall object placed 9cm in front ofa convex lens with a focal length of 3cm.

RealInvertedSmaller

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2. Find the image of a 1.5cm tall object placed 5cm in front ofa convex lens with a focal length of 3cm.


RealInvertedLarger

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Virtual, Up, Larger

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4. Find the image of a 10cm tall object placed 70cm in front ofa concave lens with a focal length of –30cm.

4. Find the image of a 10cm tall object placed 70cm in front ofa concave lens with a focal length of –30cm.


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5. Find the image of a 1cm tall object placed 4cm in front ofa convex lens with a focal length of 6cm.

5. Find the image of a 1cm tall object placed 4cm in front ofa convex lens with a focal length of 6cm.

Virtual, Up, Larger

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Lab18.2 – Lenses

- due tomorrow

Ch18 Review1. Find the image of a 1.5cm object placed 9cm in front of

a concave mirror with a focal length of 3cm.

Ch18 Review1. Find the image of a 1.5cm object placed 9cm in front of

a concave mirror with a focal length of 3cm.

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5.45.1

2. Find the image of a 2.5cm tall object placed 5cm in front ofa convex mirror with a focal length of –4cm.



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3. Find the image of a 2cm tall object placed 7cm in front of a convexlens with a focal length of 4cm.

3. Find the image of a 2cm tall object placed 7cm in front of a convexlens with a focal length of 4cm.

RealInvLarger

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5. Find the image of a 10cm tall object placed 20cm in front of a plane mirror.

5. Find the image of a 10cm tall object placed 20cm in front of a plane mirror.

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1020

2010

Documents

Ch18.1 Mirrors Concave mirror All light rays that come in parallel to the optical axis, reflect thru the focal point. All light rays that come in thru