Q&A - PSLE Science

[P5G]

Please help.


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TIA.

[Sun_2010]

19 -1)

20 -3)

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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Should the answer be A, B and D only?

TIA.

[P5G]

Please help.


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TIA.

[P5G]

Please help.


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TIA.

[andante]

atutor2001:

andante:

Hi,

For the question below, can someone help to explain why there will be burn mark on the leaf ? thx

The glass beads are acting like magnifying glass which will converge (focus) the light rays to a point on the leaf surface. The leaf with waxy surface will not get burnt because the smooth surface can reflect the light away. On the other hand, the leaf with hairy surface will absorb the light which will be converted to heat. Accumulation of heat at a single spot caused the surface to get burnt.

Hi atutor2001,
I am wondering how glass beads can act like magnifying glass(convex lens) as it is just like some form of glass material. pls advise. Thx.