11 4 The Ray Model of Light Light

11. 4 The Ray Model of Light

Light Ray A line and arrow representing the direction and straight-line path of light

Incident Light emitted from a source that strikes an object Incident Light Ray

Properties of Light When light strikes matter, it can be… 1. Transmitted – light passes through a substance 2. Reflected – light bounces off an object 3. Absorbed – light is absorbed by object and converted to heat

Flat/Plane Mirrors Image: A reproduction of an original object that is produced through the use of light Mirror A polished surface reflecting an image

Mirrors

Terminology of Reflection

Terminology of Reflection NORMAL

Terminology of Reflection NORMAL Incident Ray

Terminology of Reflection NORMAL Angle of incident Incident Ray

Terminology of Reflection NORMAL Angle of incident Incident Ray Reflected Ray

Terminology of Reflection NORMAL Angle of incident Incident Ray Angle of reflection Reflected Ray

11. 6 Laws of Reflection: Plane (flat) mirrors

Matter can be classified as: Transparent Transmits all or almost all incident light, object can clearly be seen through material Ex. Clear glass

Matter can be classified as: Translucent transmits some incident light but absorbs or reflects the rest, objects are not clearly seen through material

Matter can be classified as: Opaque Does not transmit any incident light, objects are not seen through material

Try this: Classify each of these materials as transparent, translucent or opaque: A textbook Frosted glass A single sheet of tissue paper A clean sheet of glass A rock Apple juice Sunglasses

Try this: Classify each of these materials as transparent, translucent or opaque: A textbook- OPAQUE Frosted glass- TRANSLUCENT A single sheet of tissue paper- TRANSLUCENT A clean sheet of glass- TRANSPARENT A rock- OPAQUE Apple juice- TRANSLUCENT Sunglasses- TRANSPARENT

From our lab, we learned… angle of incidence = angle of reflection The incident ray, reflected ray and the normal all lie in the same plane

Light Reflecting off Surfaces Specular Reflection: Reflection of light off a smooth surface (ex. mirror)

Light Reflecting off Surfaces Specular Reflection: Reflection of light off a smooth surface (ex. mirror)

Light Reflecting off Surfaces Diffuse Reflection: Reflection of light off a rough surface (ex. moving water)

Light Reflecting off Surfaces Diffuse Reflection: Reflection of light off a rough surface (ex. moving water)

Images in Plant Mirrors Pg 488 - Leonardo da Vinci’s handwriting

Virtual Images An image formed by light coming from an apparent light source Light is not arriving at or coming from the actual image location

Characteristics of Images in a Plane Mirror Lateral Inversion: The orientation of an image in a plane mirror that is backwards and in reverse order

Reflection Worksheet Complete the worksheet Remember that the virtual image must be the same difference from the mirror as the real object

How do we see the image?

Properties of an Image Use the acronym SALT

Sample Question

Sample Question

Sample Question S- same size A- upright L- 2 cm from mirror T- virtual