Q&A - P3 Science

[tianzhu]

The tranquil environment in this quiet thread has been disturbed by two of my answers yesterday. Please forgive me for causing ripples in the calm water.

First, I am not a trained teacher. I am just a father trying to keep in touch with primary science syllabuses so that I can guide my child when he needs it. I am also kaypoh and perhaps, brave enough to post my imperfect answers so that others can learn from my shortcomings. [quote]My purpose in teaching is to cultivate thinking & inquisitive minds, not just to produce academic results. With a thinking mind, they can progress to further studies without a tutor constantly beside them. [/quote]I totally agree with you that kids should be taught to be thinking and independent learners. They should be able learn without too much hand holding.
[quote]We are here analysing answers, trying to find logical answers, not here to point out to say someone is totally wrong [/quote]Let’s take this thread as a learning platform where parents and students exchange their ideas freely and learn from one another. We may not always come up with the so called model answers, but may offer some tips where another can tap to expand the ideas further. Along the way, mistakes will be made, but at least, we know that they are made with good intentions. We just want our kids to grow to their fullest potentials.
[quote]No human is perfect and I do not tell parents that I'm perfect too. [/quote]The answers we give in KSP are just like mirrors in the world we live in.How can there be perfect answers when we are living in an imperfect world?

[ChiefKiasu]

tianzhu:

... The answers we give in KSP are just like mirrors in the world we live in.How can there be perfect answers when we are living in an imperfect world.

Very deep, tianzhu! Your years of wisdom is definitely showing Thanks for your insights.

[tianzhu]

mrswongtuition:

I'm not sure if I'm right, but this is my conclusion:


Answer: Option 1
Reason:
Items in group A are all made of ONE MATERIAL ONLY (stated specifically for each item):
cotton towel - cotton
plastic box - plastic
paper bag - paper
Metal spoon is made of 1 material only (as stated specifically, METAL spoon).

Items in group B are made of 2 or more materials:
bicycle - metal, rubber
watch - metal, plastic, sometimes glass
umbrella - metal, fabric (nylon)
Television is made of more than 1 material (metal parts, plastic, glass)

Hope my answer is logical

Hi, Mrs Wong
Thank you for the guidance. My son and I learned something new yesterday. That’ll be two marks in the bag if this question were to appear in PSLE. A big Thank You

The consolation is we managed to get the right answer despite being clueless on the heading.I guess we are just lucky with our choice.

[tianzhu]

ChiefKiasu:

Very deep, tianzhu! Your years of wisdom is definitely showing Thanks for your insights.

Thank you for taking time to read my post.

As more MRT lines appear on face, my wife has been dropping hints that I am becoming more lor soh.

I am wise enough to recognise that life is transient, it is fragile and unpredictable. Our last breath may be taken away from us unexpectedly.I am also wise enough to know that behind every username or nick, there is a unique individual who has his/her view. They need to be treated with respect, care and dignity.

Success creates its own problems, amid growing traffic in the highly popular KSP forum, I am wise enough to know that we should be socially responsible to post answers that will guide our kids in their young journeys.

I think I better stop now, otherwise, you will be complaining, besides my wife.

[Lynn2]

can I check on this question?thanks


An ice cube was wrapped around with a wire mesh and placed in a test tube of water.The water around the mouth of the test tube was heated.After a few mins, it was observed that the water at the top started to boil.However, the ice cube remained frozen.

What can you conclude from this experiment?

Ans:water is a poor conductor of heat.

May I know why is it so?

My girl answer is the wire mesh is a poor conductor of heat.

Thanks again

[tianzhu]

Lynn2:

can I check on this question?thanks


An ice cube was wrapped around with a wire mesh and placed in a test tube of water.The water around the mouth of the test tube was heated.After a few mins, it was observed that the water at the top started to boil.However, the ice cube remained frozen.

What can you conclude from this experiment?

Ans:water is a poor conductor of heat.

May I know why is it so?

My girl answer is the wire mesh is a poor conductor of heat.

Thanks again

Hi
This is a popular question in P4.

The wire mesh prevents the ice from floating to the surface of the water.This experiment shows that water is a poor/bad conductor of heat.

Craft your answer around this concept and you should be on the right track.

[mathsparks]

Lynn2:

can I check on this question?thanks


An ice cube was wrapped around with a wire mesh and placed in a test tube of water.The water around the mouth of the test tube was heated.After a few mins, it was observed that the water at the top started to boil.However, the ice cube remained frozen.

What can you conclude from this experiment?

Ans:water is a poor conductor of heat.

May I know why is it so?

My girl answer is the wire mesh is a poor conductor of heat.

Thanks again

If water is a good conductor of heat, the heat would travel from the mouth of the test tube (where it is being heated) to the bottom of the test tube, causing the ice cube to melt. However, the iced cube remained frozen, so it can be concluded that water is a poor conductor of heat.

P.S. The wire mesh is only used to make the ice cube sink, and also, it is a good conductor of heat.

Answer provided by: Mathsparks' Son(P6)

[Lynn2]

Thanks mathsparks and tianzhu for the answer…


cheers

[ChiefKiasu]

Lynn2:

Thanks mathsparks and tianzhu for the answer...


cheers

For what it's worth, some facts:
- Water has a high heat latency, ie. it can store more heat energy before its temperature rises. This is the reason for sea breeze during the day (land heats faster than the sea) and land breeze during the night (sea cools slower than land).

- The wire mesh is a GOOD conductor of heat. It conducts away the heat of the water surrounding the ice cube so that the ice does not reach melting temperature. This is the principle of the concept of \"safety lamps\" used by miners, where the open flame is surrounded by a very fine mesh of copper wire. The copper wire cools the air (potentially highly flammable methane) surrounding the flame so that it never reaches flashpoint.

[Tang]

mathsparks:

If water is a good conductor of heat, the heat would travel from the mouth of the test tube (where it is being heated) to the bottom of the test tube, causing the ice cube to melt. However, the iced cube remained frozen, so it can be concluded that water is a poor conductor of heat.


P.S. The wire mesh is only used to make the ice cube sink, and also, it is a good conductor of heat.

Answer provided by: Mathsparks' Son(P6)

Water is a poor conductor of heat. (as water does not allow heat to travel quickly from the boiling water at the top to the ice at the bottom. Wire mesh is to hold the ice down as ice will float on water.) [Words in ( ) are not required.]