Physics Dotpoint Assignment (1 Viewer)

[StaceyK293920]

Hi there. We currently have a physics dotpoint assignment to complete. We have to choose an application related to waves and we would have to describe the physical principles within that application.

• Identify data sources, gather, process and present information from secondary sources to identify areas of current research and use the available evidence to discuss some of the underlying physical principles used in one application of physics related to waves, such as:

1. Global Positioning System
2. CD technology
3. The internet (digital process)
4. DVD technology

Choose one of the technologies listed above. Research this technology with particular reference to physics we have been discussing in this unit (e.g. the use of e/m waves and wave properties)

• Write a report of no more than one page addressing the section that has been underlined.
• Include an annotated bibliography of at least 5 references of different types

Would anyone happen to have completed the above assignment or would happen to have any ideas for me? I'm not willing to plagiarise and I will cite the source if used. Thanks.

 

[nii.kii.tahh]

Hey.
I just read your post. I think I did the same assignment on CD's in year 11.
I'll attach the information I do have.
Hopefully it'll be of help.
If worst comes to worst, Jacaranda has everything in it. It's just very brief.

Good luck =)

 

[StaceyK293920]

Hey.
I just read your post. I think I did the same assignment on CD's in year 11.
I'll attach the information I do have.
Hopefully it'll be of help.
If worst comes to worst, Jacaranda has everything in it. It's just very brief.

Good luck =)

Thank you so much nii.kii.tahh. Good luck with your HSC

 

[dpospination]

ah, this dotpoing, we just did it the other day, its pretty tricky, but if u do GPS, or current research and stuff, mayb look at the Magnetic Field positioning system they r trying to develop, good luck

 

[x.Exhaust.x]

I'm doing the same assignment as well . With CD technology, how would you talk more about wave properties? I suspect my physics teacher wants us to relate it on the 'world communicates' module e.g. wave properties. And what would be the issues for CD technology? (FOR and AGAINST)

Thanks.

 

[Aerath]

I'm not 100% sure what you're looking for but, here goes anyway.

A CD is a plastic, metal coated disc that stores information digitally as a series of pits and no pits, which are 1s and 0s respectively. This information is sread by a red laser which moves from inside out and which speed is regulated to provide a constant read rate. The pits have different degrees of reflection and as the laser can recognise this, the pits are translated into a signal and reconstructed. In audio CDs, analogue sound is transformed into a 44.1KHz encoded digital signal. Decoding circuits transform this signal into sound.

 

[x.Exhaust.x]

I'm not 100% sure what you're looking for but, here goes anyway.

A CD is a plastic, metal coated disc that stores information digitally as a series of pits and no pits, which are 1s and 0s respectively. This information is sread by a red laser which moves from inside out and which speed is regulated to provide a constant read rate. The pits have different degrees of reflection and as the laser can recognise this, the pits are translated into a signal and reconstructed. In audio CDs, analogue sound is transformed into a 44.1KHz encoded digital signal. Decoding circuits transform this signal into sound.

I'm just confused with the wavelength, the phase and the interferences part below:

A CD can be placed inside a CD player or a CD drive on computers to be read and used. A CD is read by focusing a wavelength semiconductor laser through the bottom of the polycarbonate layer. A CD stores data by a series of really small holes are burned into the surface of the master disc and duplicated on the many copies made from it. The holes are called pits and the flat places are called lands. The difference in height between pits and lands is one quarter of the wavelength of the laser light, leading to a half-wavelength phase difference between the light reflected from a pit and from its surrounding land. The destructive interference this reduces the intensity of the reflected light compared to when the laser is focused on just a land. By measuring this intensity with a photodiode (a semiconductor that converts light to an electrical signal, used in fibre optic receivers), one is able to read the data from the disc.

Would anyone be able to explain clearly in detail for more of an understanding? Or is that the best you can go, unless your a CD expert Thanks.

 

[fjnpenguin]

Hi there. We currently have a physics dotpoint assignment to complete. We have to choose an application related to waves and we would have to describe the physical principles within that application.

* Identify data sources, gather, process and present information from secondary sources to identify areas of current research and use the available evidence to discuss some of the underlying physical principles used in one application of physics related to waves, such as:

1. Global Positioning System
2. CD technology
3. The internet (digital process)
4. DVD technology

Choose one of the technologies listed above. Research this technology with particular reference to physics we have been discussing in this unit (e.g. the use of e/m waves and wave properties)

* Write a report of no more than one page addressing the section that has been underlined.
* Include an annotated bibliography of at least 5 references of different types

Would anyone happen to have completed the above assignment or would happen to have any ideas for me? I'm not willing to plagiarise and I will cite the source if used. Thanks.

wht the.. thts exactly the same question thing as my assignment...lol

 

[Aerath]

You guys use the same syllabus.

 

[x.Exhaust.x]

With CD technology, I can't find anything being discussed in depth with waves. I googled a lot of websites, and still nothing In the notes posted, there is nothing discussed in depth with waves, but there are bits and pieces of wavelength. Anyone got good wave info for CD technology? *sigh*.

Edit:

The report is due tomorrow