Agenda for 3/31/17 Grade EMS Review sheet Refraction & Diffraction Notes Test next week! HW – None

I can explain the difference between reflection and refraction. I can explain what a diffraction grating does.

Refraction of Light Placing a spoon into a cup of water causes the spoon to look distorted or shifted. Placing a pencil into a beaker of water causes distortion because of refraction Definition: the bending of waves caused by a change in their speed when they move from one medium to another. Diagram:

Refraction of Light Using a prism, you produce a spectrum. How do you know? Why does white light turn into the colors of the rainbow? Prism refracts the light twice. When it enters and when it exits. Can see colors of the rainbow.

Refraction of Light How are rainbows formed? Water acts like a prism and refracts white light (Sun)

How to catch Nemo

Diffraction of Light Definition: The bending of waves around a barrier. Diagram:

Diffraction in Water

Diffraction of Light What is a diffraction grating and what does it do? Piece of glass or plastic made up of many parallel slits. Different wavelengths allow certain colors through.

Agenda for 4/3/17 Notes on Lenses Waves Properties of Light Worksheet HW – Light Behavior Test Friday!

When you leave today… I can explain what a lens is. I can describe what the image looks like with concave and convex lenses.

Lenses Definition: curved piece of clear material that refracts light.

Two Types of Lenses Convex Concave Convex Lenses. Definition: curves out, lens is thicker in middle than on outside. Concave Lenses. Definition: curves in, lens is thinner in middle than on outside.

Write down what you see Convex Lens Concave Lens

Convex Lenses Diagram: Used to correct far-sightedness (inability to focus on objects up close).

Concave Lenses Used to correct near-sightedness (inability to focus on objects far away).

Focal Point and Focal Length the point that all parallel light rays pass through a convex lens. Focal Length: the distance from center of the convex lens to its focal point.

Wave Properties of Light incident equal reflection incidence reflected normal reflection When a wave strikes an object and bounces off, ___________________ occurs. Waves that strike an object are called _______________________ waves. Waves that bounce off are called ______________________ waves. A perpendicular line drawn from where the incident wave strikes is called the __________________. The angle between the incident wave and the normal is the angle of __________________. The angle between a reflected wave and a normal is the angle of __________________. in reflection, the angles will be ________________.

Wave Properties of Light interference light diffraction slits dark colors diffraction grating The bending of light around corners is _______________________. Diffraction results in light and ______________________ areas on the edge of a shadow. Light or sound waves can meet, causing _____________________. If light is passed through narrow _____________________, the light waves will interfere, forming dark and __________________ bands. When white light is passed through ____________, white light is separated into _______________________.

Agenda for 3/26/15 Go over Light Behavior worksheet Refraction of Light Lab HW – Waves and Light Study Guide

Light Behavior WS How is reflection of light different from refraction of light? Answer  reflection of light bounces off objects and refraction of light travels through objects. What happens to light when it goes through a prism? Explain why. Answer  develops color of the spectrum. Light is refracted twice. A __________________ contains many parallel slits that can separate white light into colors. Answer  diffraction grating Why does an object appear to be black in color? Answer  all of the colors wavelengths are absorbed. Describe why the color of our desk is tan. Answer  tan is reflected and all of the other colors are absorbed.

Light Behavior WS What are the most dangerous waves in the electromagnetic spectrum? Answer  gamma rays What colors make up the visible spectrum? Answer  ROYGBIV How is diffraction different from refraction? Answer  Diffraction – lights bends around object. Refraction – lights travels through object. Which type of lens would be used by people who are near-sighted (can’t see far away)? Answer  Concave Lenses Which type of lens would be used by people who are far-sighted (can’t see close)? Answer  Convex Lenses

Agenda for 3/22/16 Refraction of Light Lab Finish Waves and Light Study Guide Waves and Light Quiz tomorrow Unit 6 Exam next week