| What can happen if a Wave hits a Boundary? | -It can be Absorbed, which means Energy is Transferred to the Materials Energy Store [Microwaves]
-It can be Transmitted, which means it just Travel through the New Material at usually a different Speed which can mean Refraction
-It can be Reflected, so this means the Wave is just Bounced back pretty much |
| Why can a Wave be Absorbed/Transmitted/Reflected? | -This is all down to the Properties of the Wave, and the Materials that are Involved |
| What is the Simple Rule for Reflected Waves? | -That the Angle of Incidence [Direction of where it will Hit the Boundary] is Equal to the Angle of Reflection [Direction of where it will Bounce Back |
| How can this Reflection Rule be Useful? | -Light, it being Reflected onto our Eyes allows us to See Things
-When its Reflected of something Smooth, its all in the Same Direction so we get a Clear Reflection
-When its Reflected of Rough Surfaces, the Light Scatters because each Ray will hit it in a Different Angle, so is then Reflected at a Different Angle |
| What exactly is White Light? | -This is simply a Mixture of the Different Colours of Light, which all have a Different Wavelength |
| Why does a Wave, when Transmitted, travel at a Different Velocity? | -This is all due to the Materials Density, or actually Optical Density
-This can either Speed it up, or Slow it down |
| What else would Change if the Wave become Slower or Faster in the Material? | -The Wavelength would, due to the Formula of Speed=Freq x WL
-If the Wave slows down, then the Wavelength becomes Shorter
-If the Wave speeds up, then the Wavelength becomes Longer |
| What would the Change in Speed and Wavelength do to the Wave? | -This would allow the Wave to Bend; this is called Refraction
-Greater Change in Speed, the More it Bends |
| Where would the Wave Bend towards if it:
-Slowed Down
-Speeded Up | -If it Slowed down, then it would Bend towards the Normal
-If it Sped up, then it would Bend Away from the Normal |
| What would happen if:
-Sound Waves was Refracted
-EM Waves was Refracted | -Sound goes Faster in Denser Materials, so if it went from Air to Water, the Wavelength also Increases
-EM Waves goes Slower in Denser Materials, so if it went from Air to Water, the Wavelength would Decrease |
| How can the Different Colours of Light have Different Refractions? | -Since the Different Colours of Light have different Wavelengths, this means the Shortest one will bend Towards the Normal, while the Largest will be the Furthest Away |
| From Shortest to Largest, order the Colour Wavelengths: | -Violet
-Indigo
-Blue
-Green
-Yellow
-Orange
-Red |
| What is a Specular Reflection? What would it lead to? | -This is when the Waves are just Reflecting in a Single Direction from a Smooth Surface.
-This would lead to it being a Clear Reflection |
| What and How can Scattering happen? | -Scattering is simply when the Waves are Reflected in Different Directions, because of hitting a Rough Surface
-This happens because the Normal is Different for Every Incident Ray, so this means the Angle of Reflection will be Different |
| How can you Investigate Reflection? What will you find out? | -First, get a Piece of Paper, a Ray Box, a Protractor and a Mirror
1. First, draw a Line Across the Paper, and then make a Dotted Line at 90 Degrees to the Solid Line.
2. Place your Mirror in the Solid Line, and then use the Ray Box to Shin a Beam of White Light at the Mirror
3. Trace the Incident and Reflected Rays
4. Measure then those Ray's Bearing, and Record them somewhere
5. Repeat the Second Half of 2, but just change the Angle of Incidence
-What will happen is that the Angle of Incidence = Angle of Reflection. |
| For the Investigation Reflection Test, what Variables need to be kept the Same? | -Mirror
-Width
-Brightness of the Beam |
| How can you draw a Ray Diagram for Refraction? | 1. First draw the Normal when the Ray hits the Boundary
2. If the Light Ray is going into a more Denser Material, its going to bend TOWARDS the Normal. The Opposite is True
3. If the Light Ray is going through a Rectangular Block, the Incident and Emerging Ray will be Parallel
4. Use your Ruler and Arrows to show the Direction |
| In Refraction, what Determines the Angle of Refraction? | -The Angle of Incidence is one Factor
-The Wavelength of the Light, or Whatever can also Change it. If it has a Shorter Wavelength, it will Refract Further.
-The Materials on Both Sides of the Boundaries |
| How can a Prism Separate the White Light? | -Light will enter, and Bend Towards the Normal, due to Glass being Denser than Air-Since the Different Colours have Different Wavelengths, it will Bend by Different Amounts-So this means as they Leave the Prism, they will Bend away from the Normal, and the Colours will bend Differently, which means a Rainbow will come out, with Red on the Top, and Blue on the Bottom |
| Why can a Rectangular Block not Separate White Light? | -This is simply due to it having Parallel Boundaries, meaning that the Colours will bend by the Same Amount- The Emergent Ray is Parallel to the Incident Ray |
| How can you Investigate the Refraction of Light? | -First, get a Prism, Light Source, Coloured Filters and a Piece of Paper
1. Using whatever Light Source, also place a Red Filter, and then Shine a Beam towards the Prism at an ANGLE
2. Trace the Incident and Emergent Rays, and using those 2, Draw the Refracted Ray
3. Now use a Blue Filter, and Repeat 2. What you will find is that Blue will Refract More [Because it has a smaller Wavelengths]
-Changing the Shape or Materials is also another Option |
