Mr Futbol Fred

Prac: Convection Currents

Conclusion: The hypothesis was correct. The crysals sunk in the cold water but rose in the hot water.

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Prac 1- Plates that separate

1. Explain how this activity relates to the spreading at the mid ocean ridges.

Plates are moving very fast. A weak fault line causes a huge valley to form and magma fills it. The magma cools and solidifies. Old rocks get pushed out the way by new ones.

2. Identify what in your model represents each of the following:

a) Ocean floor or plate- the tables

b) the water-The paper

c) The lava flow-coloured strips

d) gravity- Pegs

e) mid ocean ridges- The part of the paper that lifts up near thr crack between the tables.

f) the magnetic strips found in rocks parallel to the mid ocean ridges-

3.  Describe what you noticed about the height of the paper as it emerged from the gap compared to the paper futher out.

The paper was higher in the middle near the crack between the tables and it went down as the paper went further out,

4. Identify which of the strips you coloured would be the for the oldest rock and which the youngest rock.

The strip right th the ends of ech paper would be the pldest rocks and the ones near the centre would be the new rocks.

5. Identify which of these strips would be the first to be swallowed by an ocean trench.

The oldest ones which were the ones furthest out would be the first to be swallowed by a trench.

Prac 2- Colliding Plates

1. Compare th above tests with plate tectonics.

These tests correspond with collision boundaries and scraping boundaries. Collision boundariesare where one plate collides with another. These are destructive boundaries since rock is melted here and is returned to the mantle for recycling. Scraping boundaries are where plates scrape along eachother. They are conservative boundaries since they conserve rock. They do not create or destroy it.

2. The stack of paper had obvious layers. Assess whether rock has layers, and of so explain why.

Rocks do have layers.

3. State which tests simulated the following collisions.

a) a continental plate with another continental plate- Test 1

b) an oceanic with another oceanic plate- Test 2

c) An oceanic plate with a continental plate- Test 3

4. Identify a place on earth where each of these collision types occur.

Places where these collision types occur are called fault lines.

1. Analyse why red sunsets can sometimes be more impressive when there is more dust or pollution in the air than usual.

When there is a high concentration of particles in the atmosphere that are slightly larger than air molecules (like smoke, dust, and pollutants), shorter and intermediate wavelengths of light (violet, blue and yellow) are scattered away. Therefore, only the longer wavelengths (orange and red) reach the observer’s eyes, giving the sun a orange-red appearance.

1. Describe what happens inside water droplets to cause a rainbow and explain how you can tell whether a rainbow is a primary or secondary.

Small droplets of water behave like tiny prisms in the sky. Sometimes the colours will reach our eyes after refracting snd undergoing total internal reflection. A primary rainbow is a band in the sky with red at the top and blue at the bottom. Sometimes a less intense secondary rainbow can be seen above a primary one. Light reahces our eyes from a secondary rainbow after two internal reflections inside each rindrop. This has the effect of reversing the colours so the bottom band is red.

a. what causes the defect?

Long-sightedness:  The exact cause of long sightedness is unknown and not well understood.

Short-sightedness: Short-Sightedness usually develops in children or young teenagers. You are more likely to develop it if it runs in your family.

b. the symptoms displayed?

Long-sightedness: Long-sightedness can cause blurred vision, headaches and tired eyes.

Short-sightedness: Short-sightedness causes distant objects to appear blurry and unfocused, while nearby objects remain in focus.

c. propose what sort of lens may be used to correct each vision.

Long-sightedness: Convex lenses are used to treat long sightedness, which are specially designed to bend the light so the retina can focus. These lenses are thinner at the edge than in the centre.

Short-sightedness: Concave lenses are used to treat short-sightedness. These are thinner in the middle.

Fibre optic technology offers many advantages when used in medical applications.

a.     describe how optical fibre may be used in medical applications

Optical fibres are used in endoscopes. These flexible tubes contain optical fibres and can be passed via the mouth into the digestive system to provide doctors with images of the stomach and intestinal lining.

b.     identify the traditional medical techniques that optical fibres might replace

Cutting open the intestines and stomach.

c.     Evaluate the benefits of fibre optic technology to medicine 

Some tumours that would otherwise be impossible to treat may be destroyed by laser light sent down an optic fibre cable inserted nearby.

1. Objectives of the mission

The objectives of this mission are to study the history of water in the Martian Arctic and to search for evidence of a habitable zone and assess the biological potential of the ice soil boundary.

2. Mission launch including spacecraft

The spacecraft used on this mission to Mars was built by Lockheed Martan.  The spacecraft will experience extreme conditons on the way to Mars, and also during the exploration of the planet. The robotic arm is another important tool on this mission. It is used to scoop up soil and water ice samples and take them to other instuments for detailed chemical and geological analysis.

3. Currents events in the mission

NASA couldn’t send commands to the Phoenix Mars lander for most of Tuesday because of a radio glitch, delaying a second day of activities, officials said.The minor problem was fixed later in the day and the Mars Reconnaissance orbiter resumed relaying the lander’s images of the Martian landscape back to Earth, said NASA officials. Phoenix, the latest spacecraft on Mars, communicates with scientists through two NASA orbiters circling the planet.