Q&A - PSLE Science

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[P5G]

P5G:

Please help.


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TIA.

Hi Auntie atutor,

My answer is (4) as I has assumed the time for D to be 13 min. Besides (3), is this also a possible answer? Your advice please.


TIA.

[atutor2001]

P5G:

P5G:

Please help.


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TIA.

Hi Auntie atutor,

My answer is (4) as I has assumed the time for D to be 13 min. Besides (3), is this also a possible answer? Your advice please.


TIA.

Hi P5G

You are correct and I am wrong. I forgot to take into account the size of the exposed surface area as shown in the picture. Great, you have keen observation skill.

[atutor2001]

P5G:

Please help.


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TIA.

My answer is (3) C where there is a slight decrease in the temperature caused by the opening of the oven door which the time actual baking started.

[atutor2001]

P5G:

Please help.


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TIA.

My answer is (2) because solar cell converts light energy to electrical energy and part of this electrical energy is converted to light energy in the display panel on the calculator.

[atutor2001]

P5G:

Please help.



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TIA.

My answer is (1) because the painted end of a compass is the north pole and will be attracted to the south pole of the other magnet.

[atutor2001]

P5G:

Please help.


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TIA.

My answer is (3) because as time goes by, more food will be digested.

[atutor2001]

P5G:

Please help.


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TIA.

To me both (1) and (3) are possible options but I will pick (1) because of the words \"after a day\".

For some seeds, it will take a long time to germinate unless we soak the seek in water first (e.g. rice grain). So I am assuming that the time needed for a seed to germinate is primarily determined by the time needed for the seed to absorb sufficient water. Therefore, in the above experiment, during the period where there is no air, it allows time for the seed to get thoroughly soaked. Once air is introduced, the seed can carry out cell respiration immediately to release energy for germination to begin.

[atutor2001]

ms_lim:

Please help to explain Qn #25 from Pei Chun 2011 Prelim, Ans key is 2 :


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If I follow the language used in the options very strictly, my answer will also be (2) because option (4) says that the candle is not strong enough - does not make sense. I am presuming that what they mean is that the \"flame of the candle\" is not strong enough.

The reason why (2) was not pick is because paper is a poor conductor of heat so it takes time to transfer heat to the water. Similarly, water is also a poor conductor of heat and will not remove heat from the paper very quickly. There is also no mention of the temperature of the water so I presume that it must be at room temperature. Therefore, heat transfer from the point on the paper (where the flame is applied) to the water will be very slow and the paper should get burnt. A more likely reason why it takes a while for it to get burnt should be that the flame of the candle is not strong enough.

(This question is quite similar to the one whereby a piece of paper is wrapped around a rod with one half made of wood and the other half made of iron. The paper wrapped around the wooden half will get burnt when a flame is brought to the centre of the rod before the iron part)