Q&A - P3 Science

[tutormum]

elkniwt:

Hi,


Need help in this Qn. Henry Park P4 2009 SA1 Paper, Qn 20.

http://www.orlesson.org/orp/09Sc/P4-09-Sc-SA1-HenryPark.pdf

The answer given is 4. My dd's ans is (2). I also think that 2 is correct. Shouldn't the air in X decrease in volume causing the ink to move towards X ??? :?

Please help. Thanks!

Your answer is correct as the cold water causes the volume of air to decrease (matter contracts when cold and expands when hot). FYI, can't trust answer sheets as mistakes abound.

[Muffins]

hi tutormum, first, the cold water will make a little of the bottle contract, making the droplet move towards Y. Then,l after about 1 minute, the air inside X will contract, causing the droplet to move towards X.

[elkniwt]

Thanks a lot!, tutormum & Muffins.

[Muffins]

you're welcome...

[tianzhu]

Muffins:

hi tutormum, first, the cold water will make a little of the bottle contract, making the droplet move towards Y. Then,l after about 1 minute, the air inside X will contract, causing the droplet to move towards X.

Hi muffin

I am wondering if you’ve ever carried out an experiment which shows that the ink droplet move to the right slightly first, then towards X when flask X is immersed in cold water

For primary science, is it necessary to elaborate that the ink droplet moves slightly to the right first? I think this information is not covered in primary textbook.

Best wishes

[Muffins]

tianzhu:

Muffins:

hi tutormum, first, the cold water will make a little of the bottle contract, making the droplet move towards Y. Then,l after about 1 minute, the air inside X will contract, causing the droplet to move towards X.

Hi Muffins,

I am wondering if you’ve ever carried out an experiment which shows that the ink droplet move to the right slightly first, then towards X when flask X is immersed in cold water.

For primary science, is it necessary to elaborate that the ink droplet moves slightly to the right first? I think this information is not covered in primary textbook.

Best wishes

Hi Tianzhu, long time no talk, buddy!

Actually, I have carried out this experiment and it is true that the ink droplet will move towards the right first, in this case.

You are also right in saying that this is not covered in the syllabus, until P5. In P5, you will have to elaborate on this quite a bit!

[tianzhu]

Muffins:

Actually, I have carried out this experiment and it is true that the ink droplet will move towards the right first, in this case.

Hi Muffins

Good Morning
It’ll be interesting to hear how you would explain why the ink drop moves slightly right first before moving towards flask X. Please share your view.

Best wishes

[ET-PH]

Thanks Tianzhu and Muffins, I couldn’t tell my dd the answer when I went through this paper with her previously. After looking at your replies (though not sure I am correct), I have explained to her that bottle X being in contact with the cold water first, contracts, pushing the ink towards Y. When the coldness propagates to the air in bottle X, the air in bottle X contracts and causes the ink to move back towards X.


Best Regards
ET-PH [/quote]

[tianzhu]

[quote]Thanks Tianzhu and Muffins, I couldn't tell my dd the answer when I went through this paper with her previously. After looking at your replies (though not sure I am correct), I have explained to her that bottle X being in contact with the cold water first, contracts, pushing the ink towards Y. When the coldness propagates to the air in bottle X, the air in bottle X contracts and causes the ink to move back towards X. [/quote]
Hi ET-PH

A good way to make science alive is to explore further by asking more questions.

First thing first, whether the ink droplet moves to the right slightly first has no relevance in answering your earlier question. This will only come into play into question such as --- What will happen to the ink drop? Explain your observation.

From my kid’s textbooks (PSLE Science 2009), I can’t recall seeing any explanation on this happening. The textbooks merely touch on the expansion of liquids and gases without elaborating on why the ink drop moves slightly in one direction before moving in the opposite way. However, if I remember correctly, there was one similar type of question in my kid’s ws and the model answer states that the ink drop moves slightly in one direction before moving towards the other.

I am not sure whether the schools expect PSLE students to describe in such details. In my opinion, there is hardly anything in primary syllabus that can help to explain this scenario.

Best wishes

[buds]

tianzhu:

A good way to make science alive is to explore further by asking more questions.

I agree with you tianzhu. Knowing the facts alone ain't enough.
It is the ability to question and analyze that will ensure that the
questions can be understood in its context properly. Cos with our
DD1 who is doing Sci for the first time this year, we have had our
share of struggles with regards to analysis and investigative work.

What we want to inculcate in her is the ability for her to ask the
investigative questions to herself, in relevance to the questions
that comes out in her assigment and her papers instead of US
parents always being around to question her to make her see
the need for analyzing..

For example... knowing the characteristics of animals alone is not
enough when it comes to answering what animal Y is... if the MCQ
states... animal Y ....

i. can fly..
ii. has hair on its body..
iii. gives birth to young alive on land..

:faint: Imagine having to ask her or rather most times \"tell her\" :x to
run through all characteristics of animals until she is able to come up
with the answer for animal Y. :faint: It can get tiring... and at times
frustrating that questioning herself isn't automatic.... yet. :xedfingers:

She is doing better of late which i do tell her, that it makes me very very
happy that she is more independent and trying to apply what we have
done together.. :love:

tianzhu:

First thing first, whether the ink droplet moves to the right slightly first has no relevance in answering your earlier question. This will only come into play into question such as --- What will happen to the ink drop. Explain your observation.

From my kid’s textbooks (PSLE Science 2009), I can’t recall seeing any explanation on this happening. The textbooks merely touch on the expansion of liquids and gases without elaborating on why the ink drop moves slightly in one direction before moving in the opposite way. However, if I remember correctly, there was one similar type of question in my kid’s ws and the model answer states that the ink drop moves slightly in one direction before moving towards the other.

I am not sure whether the schools expect PSLE students to describe in such details. In my opinion, there is hardly anything in primary syllabus that can help to explain this scenario.

To the quote in bold, hats off! :salute:

I agree whole heartedly with that! :celebrate:

There IS hardly anything much in the syllabus / textbooks to enrich the
children more on the topics they have covered... hence the need for us
(or me at least in this case.. :P) to build our Science guide library. :politebleah:

Thankfully, getting books and teaching/learning resources come as retail
therapy for me.

tianzhu:

Best wishes

I foresee having the need to consult you every now and then, tianzhu for
your logic and expertise in Math & Science is rewarding me in more ways
than one.. hehee.. not just for DD but also enriching for me personally to
be able to keep up with national education requirements and standards for children of our generation.

Best wishes to you too.
Hope you have a good week ahead. :celebrate: