Recent Changes

Thursday, January 30

  1. page Radio 3 edited ... rays indirectly, by monitoring flashes of visible light. Gamma rays are a form of radiation. …
    ...
    rays indirectly, by monitoring flashes of visible light. Gamma rays
    are a form of radiation.
    ...
    using image
    receptors

    receptors
    such as
    ...
    photographic plates.
    Now

    Now
    they use computer technology
    to generate the images produced by X-Rays.
    ...
    as these
    are

    are
    absorbed by
    ...
    they use
    balloonsand

    balloonsand
    satellites at
    ...
    high altitudes.X-Rays
    can

    can
    be indirectly
    ...
    but they
    cannot be seen by any human or animal eye.
    How might they be dangerous?
    They are extremely harmful to living creatures, which is why they're used to destroy
    cancerous cells.They cause biological harm as their rays are ironing radiation.
    ...
    cause cell
    mutation which can cause cancer or cell death. It
    can cause these illnesses as it produces radiation
    ...
    different planets.
    To scan for bone breakages or in dentists. They are also used at airports to check the luggage.
    Good work. The section radio waves deserves the merit.
    The table is incomplete - but you'll be able to see the orgers!
    Well done!
    B+ merit

    ome page>
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    4:36 am
  2. page Radio 4 edited ... Microwaves cause water and fat molecules to vibrate, which makes the substances hot. Therefore…
    ...
    Microwaves cause water and fat molecules to vibrate, which makes the substances hot. Therefore we can use microwaves to cook many types of food. Mobile phones use microwaves, as they can be generated by a small antenna, which means that the phone doesn't need to be very big. The drawback is that, being small, they can't put out much power, and they also need a line of sight to the transmitter. Microwaves are also used by fixed traffic speed cameras, and for radar, which is used by aircraft, ships and weather forcasters. The most common type of radar works by sending out bursts of microwaves, detecting the "echoes" coming back from the objects they hit (like a bat uses echo location), and using the time it takes for the echoes to come back to work out how far away the object is. They are also used to transmit data over long distances with satelites.
    Manmade radio waves have been used for a long time to send information, receive information, and to 'see' objects. Radar uses radio waves to 'see' distant objects by bouncing waves off an object and seeing how long it takes for the waves to return. Radar can even be used to find oil or see what chemicals are in soil. Radios also use these waves to send and receive information.Radio waves are used for many things today. They broadcast radio and television, communicate with satellites, let mobile phones communicate with each other, make radar systems, and allow computers to share information without wires.
    Another good piece of work. You put a lot of energy into this and it shows. Good content and formatting. The images may need explaining or having captions.
    The table is good, but rather over-full of data, as it needs to be memorisable!
    Good work.
    A- merit

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    4:35 am
  3. page Radio 2 edited ... Microwaves cause water and fat molecules to vibrate, which makes the substances hot. Therefore…
    ...
    Microwaves cause water and fat molecules to vibrate, which makes the substances hot. Therefore we can use microwaves to cook many types of food. Mobile phones use microwaves, as they can be generated by a small antenna, which means that the phone doesn't need to be very big.Microwaves are also used by fixed traffic speed cameras, and for radar, which is used by aircraft, ships and weather forcasters. The most common type of radar works by sending out bursts of microwaves, detecting the "echoes" coming back from the objects they hit (like a bat uses echo location), and using the time it takes for the echoes to come back to work out how far away the object is. They are also used to transmit data over long distances with satelites.
    They can be used for AM radio, FM, radio,TV, mobile phones and things like the police.
    Good work. Not the easiest topic to find good material for but you have done well. Not sure if all of the images are useful and they all need explanations or captions - even if they are labelled - to explain why they are there.
    Nice formatting on the table.
    Well done!
    A-

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    4:33 am
  4. page Radio 1 edited ... in mobile phones. Antennas designed ... detect radio waves are usually similar in siz…
    ...
    in mobile phones.
    Antennas designed
    ...
    detect radio
    waves are usually
    similar in size to
    the wavelength
    they want to detect.
    How might they be dangerous?
    ...
    substances hot.
    Communications
    Very good work. You have made good use of images (remember to explain or caption them). The content is just right.
    The table has been done well.
    Well done!
    A-

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    4:31 am
  5. page Microwaves 4 edited ... Heating food Communications Very good work. The content is just right and the images work w…
    ...
    Heating food
    Communications
    Very good work. The content is just right and the images work well (remember to caption or explain each one),
    The table is good - as it doesn't have too much information.
    Well done!
    A-

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    4:29 am
  6. page microwaves 3 edited ... transmitter Radio waves are ... waves that are generated by a transmitter. How are th…
    ...
    transmitter
    Radio waves are
    ...
    waves that
    are generated by a transmitter.
    How are they
    ...
    test for them.
    Antennas designed to
    ...
    waves are
    usually similar in size
    ...
    wavelength they
    want to detect
    How might they be
    ...
    preventing you from
    seeing clearly.
    ...
    are not
    dangerous

    dangerous
    because
    they have a low
    frequency.
    ...
    information from one
    place to another and
    ...
    to heat
    food

    food
    up in microwave
    ovens
    ...
    be used
    for transmitting sound
    and television signals,
    ...
    for the
    transmission of data
    in coded form.
    Good work. You have selected good material for the microwaves section and the well chosen imges work well.
    The table has some formatting issues but the content is good.
    A-

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    4:27 am
  7. page Microwaves 2 edited ... {http://static.ddmcdn.com/gif/cell-phone-radiation-transm.jpg} How do we detect them? ... …
    ...
    {http://static.ddmcdn.com/gif/cell-phone-radiation-transm.jpg}
    How do we detect them?
    ...
    Geiger Tube - really?
    {http://www.alpha-crucis.com/2000-2490-thickbox/geiger-tube.jpg}
    What can they be used for?
    ...
    -Manmade radio waves have been used for a long time to send information, receive information, and to 'see' objects. Radar uses radio waves to 'see' distant objects by bouncing waves off an object and seeing how long it takes for the waves to return. Radar can even be used to find oil or see what chemicals are in soil. Radios also use these waves to send and receive information. -Natural radio waves were first discovered in the 1930s by Karl Guthe Jansky, working for Bell Laboratories. Before his discovery, everyone thought only people could generate radio waves. Bell was detecting static on his radio channels, and had Jansky try to figure out where this static, or interference was coming from. Surprisingly, the interference was coming from space! This discovery eventually led astronomers to look at radio waves along with optical waves to find things in the sky. These radio astronomers use giant Radio telescopes, shaped like satellite dishes, to gather and analyze the waves.
    -Radio waves are used for many things today. They broadcast radio and television, communicate with satellites, let mobile phones communicate with each other, make radar systems, and allow computers to share information without wires.
    Good work. You put in a decent amount of effort into the microwaves section. Some formatting would need to be ironed out, but the overall effect is good.
    The table is rather over-full - it needs to be memorable!
    Well done!
    A-

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    4:26 am
  8. page Microwaves 1 edited ... rays is the sun however man made lamps can also ... create stronger, more concentrated…
    ...
    rays is the sun however man
    made lamps can also
    ...
    create stronger,
    more concentrated rays.
    They just appear
    ...
    large stars
    and in mobiles
    ...
    made with
    a transmitter chip
    Radio waves make up part of the
    ...
    waves are packets of energy with
    differing wavelengths, similar to
    ...
    X-rays or
    Gamma rays, except longer
    How are they detected?
    ...
    accurate among
    image receptors.
    ...
    you can
    simply use a filtratethis is
    the cheepest option and
    ...
    as thisyou could use a UV
    dectector, theycome in a
    ...
    and prices.
    As with most things, the
    more you pay
    ...
    us see warm objects emitting
    this type of energy.
    ...
    receivers if
    they

    they
    are used in mobile
    phones
    Antennas designed to detect radio
    waves are usually similar in size to the
    ...
    to detect.
    This

    This
    is why
    ...
    radio antennas
    have to be very long. If the antennas
    are not close to the size of the
    ...
    to produce more
    damaged cells.
    ...
    dangerous as
    they damageand kill cells.
    When this happens to
    ...
    sun burn.
    It happenswhen our skin has
    seen a lot of sunor due to a
    ...
    can damage the cataract.
    radio waves are not dangerous because
    ...
    Large doses
    of

    of
    radio waves
    ...
    cause cancer,
    leukaemia

    leukaemia
    and other
    ...
    Some people
    claim

    claim
    that the
    ...
    field from
    overhead power cables near their homes has affected their health.
    What are the main or most significant uses?
    ...
    bones to reveal any
    irregularities
    ...
    be used
    for

    for
    tanning, in
    ...
    bed or
    by the sun.
    We use light to sense
    what is around us, it
    enables us to see objects and generally survive.
    ...
    the most
    dangerous of the types of radiation.
    It is able to burn you but it is more
    ...
    heating up food and in
    mobile phones
    ...
    AM radio,
    FM, radio,TV, mobile phones and
    things like the police
    Very good work indeed. The material is appropriate and the presentation is very good. The table is sound - but with some odd phrasing (pasted)?
    Overall, excellent.
    A- merit

    <Home page> ALL IMAGES ARE FROM GOOGLE IMAGES.
    (view changes)
    4:23 am
  9. page IR 4 edited ... cooking,heating,communtication siganals,tv remote controls they are used to transfer informat…
    ...
    cooking,heating,communtication siganals,tv remote controls
    they are used to transfer information
    Good work. The content is fine, and you have done well with the formatting.
    The table is also well populated and easy to learn.
    B+ merit

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    (view changes)
    4:20 am
  10. page IR 3 edited ... {http://ts2.mm.bing.net/th?id=H.4605138191122865&w=232&h=136&c=7&rs=1&pid=…
    ...
    {http://ts2.mm.bing.net/th?id=H.4605138191122865&w=232&h=136&c=7&rs=1&pid=1.7}
    What are they?
    ...
    than visible toilet.light.
    it was discovered by william herschel in 1800.
    over half of the energy that arrives at earth is in IR form
    ...
    for food in microwaves and in mobile phones
    transmitting sound
    Good effort - but I think there is more material out there to find!
    The table is complete but, again, it could enjoy a bit more information.
    Overall, well done!
    B+

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    (view changes)
    4:18 am

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