Q&A - PSLE Science

[tianzhu]

benleetube:

Hi, I just wanted to ask this question out of curiosity. How is natural wind formed? And by natural, I mean it is not created by fans, etc.


Thanks.

Hi

Hope this helps.

http://itehome.apogee.net/kids/?ver=kkblue&utilid=itehome&id=16208

Best wishes

[tianzhu]

Kloggy:

Hi, can someone help with the following:


An experiment was carried out by placing duckweeds in two beakers with 500ml of water each. 10 ml of bleach was added to one of the beakers. Write an hypothesis for the experiment.

The answer provided was that the duckweed will grow better in the water with bleach added. But why ?

Thanks.

Hi

In answering this question, a student needs to have a good understanding of “What is a hypothesis?”

He or she needs not venture too far; a good explanation is given in PSLE Science Guide (MC).

A hypothesis is an educated guess; it is what you predict the results of an experiment will be.

A hypothesis may or may not be correct.

For more reading, you may refer to this link.
http://primary-school.helium.com/how-to/9563-how-to-write-a-hypothesis

Judging from the information you have provided, I guess that the person carrying out the experiment wants to find out if duckweeds grow well in water containing bleach.

How does the amount of bleach added to water (independent variable) affect the growth of duckweeds (dependant variable)?

I’d go for

a)If the amount of bleach added to water is increased, then the duckweeds will grow faster. or b) The amount of bleach added to water affects how well the duckweeds grow.

Best wishes

[benleetube]

tianzhu:

benleetube:

Hi, I just wanted to ask this question out of curiosity. How is natural wind formed? And by natural, I mean it is not created by fans, etc.


Thanks.

Hi

Hope this helps.

http://itehome.apogee.net/kids/?ver=kkblue&utilid=itehome&id=16208

Best wishes

Thank you master

[hashroop]

benleetube:

hashroop:

[quote=\"Nebbermind\"]i think the circulatory gwah. That wld be the main mean to transfer nutrients from mom to foetus for it to build the rest.

thank you, but Im not too sure of the right order.Sometimes I think its the skeletal that should come first to support the growing foetus.Im just lost :? Im waiting for the centre to release the papers to see what is the correct answer. Once received I'll definitely post up here for sharing purpose

rgds

Hi,
I think this website may help:
http://in.answers.yahoo.com/question/index?qid=20100922035844AAHry4J[/quote]Hi, teacher went thru the paper and its circulatory,respiratory,skeletal and digestive, in that order.

[jesschan]

Hi! Is it true that at primary school level, for terminology on electricity topic, we should use electrical insulators / non-conductors of electricity and avoid using the term "poor conductor of electricity" unlike topic on heat where the reverse is true i.e we should say poor conductor of heat instead of using the term "insulator"?

[bobsg01]

P6 Science


How to explain the sunset that Annie is at position 2 (which is the ans)? :scratchhead:

Thanks in advance.

http://i56.tinypic.com/2eo8so5.jpg\">

[tianzhu]

Hi bobsg01


I think, effective 2010, the Solar System is no longer in the PSLE Science syllabus.Please confirm it with your school teacher. It’s good news for the Solar System is not an easy topic to grasp for many PSLE students.

The Earth rotates on an imaginary axis from West to East. It takes about 24 hours or 1 day to complete one rotation.

At any one time, only one side of the Earth is facing the Sun. The side facing the Sun will experience daytime. The side that faces away from the Sun will experience night time. Hence, the Earth’s rotation gives us day and night.

Position 2 is a logical answer. Annie is experiencing sunset now because as the Earth rotates, the side facing the Sun will be rotated away from the Sun.

Best wishes

[bobsg01]

Thanks tianzhu, will definately check.

http://i56.tinypic.com/i4itdf.gif\">

[P5G]

Please help.


Question 10.
Simon completely filled two identical syringes, one with air while the other with water, and covered them with black paper as shown in the diagram attached.
http://www.orlesson.org/orp/10Sc/2010-P6-Sc-SA2-ACS.pdf

He then pushed each plunger as hard as he could and measured the distance, x.
Which one if the following shows the correct values of x?

Syringe with water (x / cm) /// Syringe with air (x / cm)
(1) 10 /// 0
(2) 0 /// 10
(3) 10 /// 7
(4) 7 /// 10


Question 40a.

The answer given uses 'plant without roots' for the control set-up.
Should the 'plant without leaves' be used for the control set-up instead?

Please advise.

TIA.
Is the answer given (1) correct?

[P5G]

Please help.


http://www.orlesson.org/orp/10Sc/2010-P6-Sc-SA2-CHS.pdf


Should the answer for question 9 be (4) instead of (2) as given?

Please advise how to get the answers for questions 14, 17, 23 and 27.


TIA.