Jason

Practical 3 – ‘Convection Currents’

Conclusion Convection Currents- Part A

The hypothesis I had planned turned out correct. I predicted we would successfully observe the movement of convection currents. The crystal had released purple coloured dye into the water. The dye had spun around also rising in the water as the convection current. The dye had risen due to the fact that the heat caused the dye to become more lighter and less dense than the water.

Conclusion Convection Currents- Part B

The crystals did realeased dye into the water. The cold air from the bag of ice had pushed and caused the dye to sink to the bottom of the beaker where it circulated. The cold air had made the dye heavier and more dense than the water which is why the dye had fallen to the bottom of the beaker.

Questions

1. Explain what causes convection currents.

Convection currents are caused by activity between hot air and material and cold air and material. In the mantle hot air, liquids and molten rock rise whereas cool air, liquid and rock sink due to their higher density. When hot mantle rock comes into contact with relatively cold crust, it cools and sink. This is what causes convection currents in the mantle.

2. Use a diagram to clarify what a ‘hot’ current does.

3. Identify the direction of a ‘cold’ current.

A cold current sinks and travels in an anti-clockwise direction. The cold current is the opposite of a warm current which spins in a clockwise direction.

Practical 1 – ‘Plates that seperate’.

Conclusion

In the end my hypothesis was correct, we have successfully modelled the mid-ocean spreading tectonic plates in the classroom. From this practical we learn that when two plates have seperated new rock is formed and old rock is pushed further out. The new rock (Magma & heated material) is pushed out of the faultline and is then cooled down by the ocean water, solidifying it and causing it to sink down as newly formed rock.

Questions

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

Just like a mid-ocean ridge, the two plates are replaced by two desks and the magma or new rock is replaced by the paper. As the paper is pushed out and spreads outwards with a downward slant it reanacts what exactly happens underwater when plates seperate underwater.

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

a. Ocean floor or plate- The desk

b. The water- The desk

c. The Lava Flow- The layers coloured on the paper

d. Gravity- The force of your hand

e. Mid-ocean ridge- The split in the middle

f. Magnetic strips found in rocks parallel to mid ocean ridges- Parallel to the lines drawn

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

As the paper came out it rose high but then started to slant downards as it came out symbolising the magma being cooled into rock and the rock slowly falling down to the ground. The further the paper went the lower it became till it couldn’t get any lower.

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

The strip the furthest away from the split would be the oldest rock and the ones closest would be the youngest rock. When new rock is formed they push the old rock out further.

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

The oldest strips would be the first to be swallowed by a trench. As they are first in line towards a trench and infront of all the other new rock.

Practical 2 – ‘Colliding plates’

Conclusion

My hypothesis for this experiment was correct, we have properly modelled what happens when two tectonic plates collide. This experiment teaches us how when pates collide, landmass can be pushed in a variety of directions depending on the factors. It gives us a practical representation of plate tectonics.

Questions

1. Compare the above tests with plate tectonics.

Each test represents a type of plate tectonics (i.e collision boundary). The first test shows a plate colliding with another plate which causes folds of mountains. The second one shows a faster plate going below a slower plate which can cause the some islands to be formed. The third one shows a continental plate going over a oceanic plate because an oceanic plate is more dense and heavy.

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

Rocks do have layers, different layers can be made from minerals or other substances i.e. fossils collected on the rock.

3. State which tests simulated the following conditions:

a. Continental plate wiht another continental plate- Test 1

b. An oceanic plate 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 occurs.

Test 1- Asia (Himalayan region)

Test 2- Indonesia

Test 3- Andes Mountain range

1. Analyse why red sunsets can sometimes be more impressive when there is more dust or pollution in the air than usual. This happens because the sunlights rays are broken up and also reflected in and around the millions of particles of dust and other tiny solids in the air giving the sun it’s impressive colours during sunset.

2. Describe what happens inside water droplets to cause a rainbow and explain how you can tell whether a rainbow is a primary or secondary. When the sun shines onto raindrops light is refracted out as a spectrum on light, which in turn creates the big rainbow we see.

Investigate the two types of sight defect; long sightedness and short sightedness.

Find the following information:

1. What causes the defect?
Long sightedness: The causes are not exactly known but some cases are beleived to be caused because it is hereditary.
Short Sightedness: Light focuses infront instead of behind the eyes retina and a blurred image is created. Can be caused by certain drugs or if it runs in your family.

2. The symptoms displayed.
Long sightedness: You are unable to focus, particularly on objects upclose and are seeing objects as blurry.
Short Sightedness: You are unable to focus upon distant objects, they appear blurred. Nearby objects remain clear and unchanged.

3. Propose what sort of lens may be used to correct each vision.
Long sightedness: Glasses & contact lenses are commonly used.
Short Sightedness: Glasses & contact lenses are commonly used.

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

Describe how optical fibre may be used in medical applications – Fibre optics are used as guides in medical procedures or operations, they provide a precise and accurate small light source when operating on patients.

Identify the traditional medical techniques that optical fibres might replace – Optical fibres may replace the current form of communication within hospitals to provide a faster way of communicating across and around the hospital.

Evaluate the benefits of fibre optic technology to medicine – Fibre optics provides more than satisfactory light vision in inclosed medical surgeries in and around the body possibly saving lives in the process.

a) Research the qualifications and training required to be an astronaut
To become an astronaut a person must be physically and mentally fit. An astronaut must also be trustworthy, be reliable and have great communication skills. Finally an astronaut must be able to speak english and russian if landing on the Mir space station.

b) Research a current astronaut under the following headings
Name
Employer
Training
Country of residence
Past missions
Future missions

NASA has recently launched the phoenix mission. Research this mission under the following headings.
1. Objectives of the mission
The objectives of the phoenix mission was to search for life and/or water on mars.

2. Mission launch including spacecraft
Mission launch proceeded in August 4th in 2007. The spacecraft is classified as a lander and was called phoenix hence the name of the mission.

3. Currents events in the mission
There have been interesting events that have occured during this mission, one of those include the finding of shallow subsurface water ice which has been proven and suggests that there may be or has been life on the planet.

The movie ” Contact ” stared Jodie Foster as an astronomer who discovers signals from extraterrestrial intelligence and later makes contact. This character is rumoured to be based on a real – life SETI researcher, Jill Tarter. Research Jill’s contribution to the SETI program

Investigate other theories of the origin of the universe or suggest your own.
The Christian/Catholic religion beleive that God created the heavens and the earth, water and land, creatues and animals, humans and trees. Opposing the theory of the big bang proposed by Edwin Hubble. In the hindu religion there are many versions of the worlds creation one of them depict a god called Vishnu and servant Brahma. They beleive Brahma created earth and all it’s characteristics.

Research more about the Hubble Space Telescope. Gather information about
a) Hubble’s involvement in space research
Hubble was an american astronomer, he increased astronomers’ understanding of the universe by discovering other galaxies besides the milky way, detailed characteristics of redshifts etc.
b) What the space telescope does
The hubble space telescope has become one of the most important science projects ever, the telescope has gathered an estimated 260, 000 astronomical observations to date and 13, 000 astronomical objects have been observed by hundreds of groups of scientists.
c) Where it is
Currently at 12:03pm May 20th the telescope is just east of the U.S., but travels at 5 miles per second so will not be there for long.
d) What Hubble’s constant is
H0 is Hubble’s constant and corresponds to the value of H. Hubble’s constant is a statement in physical cosmology it explains that the redshift in light coming from distant galaxies is proportional to their distance.