Big question (1 Viewer)

zeebobDD

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A physics student made the following statement:

On earth, the acc due to gravity is a constant value of 9.8m/s^-2

Discuss the students statement: (6 marks)
 

nightweaver066

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Points to address:
- Correct/Incorrect?
- What affects acceleration due to gravity(mass/altitude/density/geographical location/centrifugal)
Talk about each point and don't simply list them (6 marker, remember).
E.g. mass - Newton's law of gravitation, *explanation*
- Greatest at poles, weakest at equator
- For simplicity, we take gravity to be 9.8m/s^2 but it is NOT constant due to the above factors

Thinking of anything else..
 

Gujju

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You can talk about these points:-

Points against
- the lithosphere shows variations in thickness and structure due to factors such as tectonic plate boundaries and dense mineral deposits. These variations can alter the values of g

- earth isnt a perfect sphere, it is flattened at poles and results in less value of g at poles than at equator.

- because the earth is spinning, it creates a centrifuge effect just like when we are on a merry-go-round...when we are right in the centre we feel safe but when we are close to the edge, we fear of falling out...so same thing with earth...at poles would be like to sit in the centre and at equator it would be like close to the edges so the gravity value would be less at equator...
EDIT- gravity also decreases as we gain altitude
Only point for
even if we take the above mentioned points into account, the value of g changes its value at like 6th decimal place which is negligible and makes no difference

​this is my first post yay!
 

viraj30

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You can talk about these points:-

Points against
- the lithosphere shows variations in thickness and structure due to factors such as tectonic plate boundaries and dense mineral deposits. These variations can alter the values of g

- earth isnt a perfect sphere, it is flattened at poles and results in less value of g at poles than at equator.

- because the earth is spinning, it creates a centrifuge effect just like when we are on a merry-go-round...when we are right in the centre we feel safe but when we are close to the edge, we fear of falling out...so same thing with earth...at poles would be like to sit in the centre and at equator it would be like close to the edges so the gravity value would be less at equator...
EDIT- gravity also decreases as we gain altitude
Only point for
even if we take the above mentioned points into account, the value of g changes its value at like 6th decimal place which is negligible and makes no difference

​this is my first post yay!
very detailed!
 

zeebobDD

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cheers guys :) for the 6 marks, you needed 2 points against and 1 for the argument , + the identification of factors, explanation etc
 

nightweaver066

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You can talk about these points:-

Points against
- the lithosphere shows variations in thickness and structure due to factors such as tectonic plate boundaries and dense mineral deposits. These variations can alter the values of g

- earth isnt a perfect sphere, it is flattened at poles and results in less value of g at poles than at equator.

- because the earth is spinning, it creates a centrifuge effect just like when we are on a merry-go-round...when we are right in the centre we feel safe but when we are close to the edge, we fear of falling out...so same thing with earth...at poles would be like to sit in the centre and at equator it would be like close to the edges so the gravity value would be less at equator...
EDIT- gravity also decreases as we gain altitude
Only point for
even if we take the above mentioned points into account, the value of g changes its value at like 6th decimal place which is negligible and makes no difference

​this is my first post yay!
Feels like i'm bumping up such an old post lol.

Just a slight error with your last point, the value of gravity varies between 9.76m/s^2 and 9.83 m/s^2 (at equator & poles respectively), not at the 6th dp.
 

someth1ng

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Remember, discuss means for/against but for each point, you need to identify, describe and explain.
 

Fizzy_Cyst

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Remember, discuss means for/against but for each point, you need to identify, describe and explain.
THIS! Don't just list the for/against, make sure you go further!

Also, Discuss is for and/or against, so it may not be practical to do both -- but if you can, definitely do.
 

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