Journal Writing Activity Write a paragraph that includes a definition and example of transparent , translucent and opaque light.

Reflection The bouncing of a wave of light off of a material When light is dispersed a reflection can occur. Dispersion – separating into layers

Light is the form of energy which What is LIGHT? Light is the form of energy which gives the sensation of sight. No Light – No sight Examples: REFLECTION, REFRACTION, DISPERSION, SCATTERING etc.

Rainbows A rainbow is formed due to the dispersion of sunlight caused by tiny droplets of water present in the atmos- phere. A rainbow is seen just before or after rain.

Refraction The changing of the path of a wave as it moves between materials Light passes through all transparent media as well as the vacuum of space

Refraction When light enters from one medium to another, it suffers a change in its path, caused by the difference in its speed. The changing of the path of a wave as it moves between materials

Refraction (Cont.) www.jnvkannur.temple.at

Refraction of Light Refraction – Bending of light due to a change in speed. Different frequencies are bent different amounts & light is broken out into different colors.

Prism – Glass that bends light Prism – Glass that bends light. Different frequencies are bent different amounts & light is broken out into different colors.

Electromagnetic Spectrum Visible Spectrum – Light we can see Roy G. Biv – Acronym for Red, Orange, Yellow, Green, Blue, Indigo, & Violet. Largest to Smallest Wavelength.

Can It Reflect Light? What types of objects or materials can reflect light? Put an X next to the things you think can reflect light. Explain your thinking. Describe the “rule” or the reasoning you used to decide if something can reflect light. ___ red apple ___ rough cardboard ___ the Moon ___ rusty nail ___ clouds ___ soil ___ wood ___ milk ___ bedsheet ___ brand new penny ___ old tarnished penny ___ smooth sheet of aluminum foil ___ water ___ gray rock ___ leaf ___ mirror ___ glass ___ sand ___ potato skin ___ wax paper ___ tomato soup ___ crumpled paper ___ shiny metal ___ dull metal

Mirrors and Reflection When light rays are reflected in a mirror, the image appears the same distance from and along the perpendicular to the mirror line. This makes it possible to determine the lines of symmetry in objects that are symmetrical. Mirror Twins

Transparent, Translucent, Opaque Sometimes rather than reflecting off an object, light will travel through an object. Transparent: All light goes through the object. (air and water) Translucent: Some of the light travels through the object. Opaque: Light cannot travel through object. Light Traveling Through Objects

The Refraction of Light When light travels from some transparent substances through others –like air into water or glass into air, the light bends. Convex Lenses Concave Lenses Prisms

A lens is a curved piece of clear material that refracts (bends) light in a specific way There are two main types of lenses – convex or converging lens and concave or diverging lens. Convex lens- thicker a center than edges bends light toward each other Concave lens- thinner at center bends light waves away

Convex Lenses A magnifying glass is an example of a convex lens. A convex lens is thicker in the middle of the lens than it is at the ends. A convex lens bends the light and makes the object look larger or magnify it.

Concave Lenses A concave lens is thinner in the middle than at the ends. Concave lenses cause the light to spread out after light passes through them. Concave lenses are used in glasses for people who are short-sighted or cannot clearly see things far away.

Baby Soda Bottle Lenses Fill with three fourths water. Put the cap on securely. Turn the bottle sideways over print. Look through the curve filled with water and the bubble formed by the air.

Prisms A prism bends the light in such a way that it separates it into different parts. Normal white light contains all the colors of the rainbow. Prisms can separate the different colors because each color bends differently when it passes through a prism.

Translucent Materials A translucent material scatters light as it passes through. We can usually see something but behind a translucent object, but the details are blurred. Wax paper and frosted glass are translucent materials.

The Color of Objects The color of any object depends on the material the object is made of and the color of light striking the object. Color of Opaque Objects The color of an opaque object depends on the wavelengths (colors) of light that the object reflects. Every opaque object absorbs some wavelengths of light and reflects others. The color of an opaque object is the color of light it reflects.

Color of Transparent and Translucent Objects Materials that are transparent or translucent allow only certain colors of light to pass through them. They will reflect or absorb the other colors. The color of a transparent or translucent object is the color of the light it transmits. Often we make color filters out of these.

Additional Terms Frequency – the number of wavelengths that pass through a point in a given second Wavelength – the distance between the wave’s crest Crest – the top of the wave Trough – bottom or deepest part of wave

Resources Brainpop - Types of Waves Brainpop - The Eye Brainpop - Color