Posterous theme by Cory Watilo

 

 

3.9

10 February 2011

14:52

·         3.9 understand that waves can be diffracted through gaps, and that the extent of diffraction depends on the wavelength and the physical dimension of the gap

 

Diffraction by a gap

·         Most of the wave passes straight through the gap

·         But the sea wall causes diffraction at the edges of the wave

·         Note that the wavelength is the same before and after diffraction

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·         Diffraction is at a maximum when the width of the gap is equal to the wavelength of the wave

·         The plane waves are now completely curved

·         Note that the wavelength is the same before and after diffraction

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Website http://www.falstad.com/ripple/

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Diffraction patterns in the sea

 

 

 

3.9 Plenary Answers

10 February 2011

14:52

PFY p.178 Q.2

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(download)

 

 

3.8

10 February 2011

14:52

·         3.8 understand that waves can be diffracted when they pass an edge

 

Website http://www.falstad.com/ripple/

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3.10 and 3.11 starter

27 February 2012

15:17

·         Do you know the 7 colours of the visible spectrum?

·         Can you put them in order from longest to shortest wavelength?

Answer

1.            Red (longest wavelength)

2.            Orange

3.            Yellow

4.            Green

5.            Blue

6.            Indigo

7.            Violet (shortest wavelength)

 

How can you remember the order?

Richard Of York Gave Battle In Vain!

 

 

3.10 and 3.11 starter 2

27 February 2012

15:17

·         Do you know the 7 parts of the EM spectrum?

·         Can you put them in order from longest to shortest wavelength?

Answer

1.              Radio (longest wavelength)

2.              Microwaves

3.              Infrared

4.              Visible

5.              Ultraviolet

6.              X-rays

7.              Gamma rays (shortest wavelength)

 

Can you make a mnemonic to help you remember the order?

by Remembering Mnemonics I ...

 

 

3.10 and 3.11

10 February 2011

14:44

·         3.10 understand that light is part of a continuous electromagnetic spectrum which includes radio, microwave, infrared, visible, ultraviolet, x-ray and gamma ray radiations and that all these waves travel at the same speed in free space

·         3.11 recall the order of the electromagnetic spectrum in decreasing wavelength and increasing frequency, including the colours of the visible spectrum

EM Spectrum – speed, wavelength and frequencies

<<EMFlash[1].swf>>

 

 

3.10 and 3.11 plenary

10 February 2011