Q&A - P3 Science

[underthesea]

tianzhu,


dd’s teacher has not returned the science paper nor discussed the questions in class. I am waiting for the teacher’s answer also. Will definitely share the answer here.

[tianzhu]

underthesea:

Becky has some coffee powder. She kept half of it in an air-tight container and the other half in a plastic bag. After one week, Becky observed some changes.


Q1: What do you think will Becky observe after a week?

Q2: Explain your answer in Q1.


This is a P4 CA1 question, please help. I know the coffee powder in the plastic bag will be harden but don't know why. Something to do with the air....??

TIA.

Hi

I think moisture in the air will cause the coffee powder to clump if you do not keep the container tightly sealed. Some of the powder in the plastic bag will cluster together to form clustered masses or lumps.

Best wishes

[jesschan]

Can anyone advise - cabbage is which part of the plant?

[Muffins]

It is the leaf of the plant I think… A whole ball of leaves…

[jesschan]

Thanks, Muffins. I thought so as well but wasn’t very sure…

[underthesea]

ET-PH:

Hi, I would think the answer is A. In this experiment, the water level has raised to 125ml from 100ml, the stone has occupies the space in the water. The experiment do not show or prove that the stone has a definite volume, though the stone (a solid) has a definite volume. Hope I am right.

I have asked a few other parents and also asked dd to check with her teacher. The correct answer should be \"B - the stone had definite volume\".
We only say the stone occupies space if water spill out from the beaker, ie the stone replaces the space taken by the water.

[ET-PH]

I m sorry to give you the wrong answer. I really can't think why the answer is \"the stone has a definite volume\". The stone has a definite volume (without the experiment), but in the context of this experiment, the water raised from 100ml to 125ml basically shows that the water has been displaced by a matter which occupies space. :?

[ChiefKiasu]

ET-PH:

I m sorry to give you the wrong answer. I really can't think why the answer is \"the stone has a definite volume\". The stone has a definite volume (without the experiment), but in the context of this experiment, the water raised from 100ml to 125ml basically shows that the water has been displaced by a matter which occupies space. :?

We will quickly come to realize that Primary School Science is about using the right terms for the specific question. \"Definite volume\" is a term the kids learnt in school to refer to solid matter that has a definite shape (as opposed to liquids or gases). All matter occupies space. So while in common terms the displacement of water is due to the stone taking up \"space\" in the water, the correct answer is that the experiment demonstrates that the stone has a definite volume.

[atutor2001]

ET-PH:

I m sorry to give you the wrong answer. I really can't think why the answer is \"the stone has a definite volume\". The stone has a definite volume (without the experiment), but in the context of this experiment, the water raised from 100ml to 125ml basically shows that the water has been displaced by a matter which occupies space. :?

Hi ET-PH

The experiment shows that the stone has a \"definite volume\" because the raised water level REMAINS at 125 ml.

If the stone does not have a definite volume, then the water level will not stay at 125 ml but will move up and down above the 100 ml mark.

[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!