PSLE 2012 - Science

[wsywin2012]

concerned_of_PSLE 10:

I thought should be anther because the stigma may be pollinated beforehand without pollen grain fertilisation cannot happen

cross-pollination (pollen grains from other flowers) can still occur.

[creamyhorror]

atutor2001:

James Ang:

The use of fans creates wind which is moving air and the presence of wind increases the rate of evaporation and produces a greater cooling effect.

Fan is used to disperse the mist to reach different parts of the room so that the room will cool down at a faster rate. It is also to prevent the tiny water droplets from combining into large droplets (precipitation like rain cloud) that would fall to the floor and wet the room.

I think all 3 points are correct. Higher air movement inherently results in an increased evaporation rate.

Sounds like this year's paper had a few challenging application questions. Hope my brother figured something out, especially for that interesting frog/tadpole question :skeptical:

[Big fish]

concerned_of_PSLE 10:

I thought should be anther because the stigma may be pollinated beforehand without pollen grain fertilisation cannot happen

My ds wrote anther, so I am confused by the stigma answer, any science teacher bor, can help????????? :? :? :?

[Big fish]

GLORYmum:

Big fish:

Tks. That is the problem of having 2 threads. Don't know where to see.

Pls discuss here lah.

我滚回来了！！！！！ :shock: :shock: :shock:

[GLORYmum]

Big fish:

GLORYmum:

[quote=\"Big fish\"]Tks. That is the problem of having 2 threads. Don't know where to see.

Pls discuss here lah.

我滚回来了！！！！！ :shock: :shock: :shock:[/quote]



好大的风呀！！

[vaidyanathan padmini]

How about friction question from McQ…

My dd’s answer is only C as friction opposes motion…
Only the box in c is moving so it should have friction

[ultimateschooler]

Stigma

[ximinful]

vaidyanathan padmini:

How about friction question from McQ.....

My dd's answer is only C as friction opposes motion...
Only the box in c is moving so it should have friction

My ans is B&C but it seems like many have written A as well.

[moonee]

vaidyanathan padmini:

How about friction question from McQ.....

My dd's answer is only C as friction opposes motion...
Only the box in c is moving so it should have friction

according to the teachers and friends of my dd, the answer is A B and C. Cfmirm

[concerned_of_PSLE 10]

vaidyanathan padmini:

How about friction question from McQ.....

My dd's answer is only C as friction opposes motion...
Only the box in c is moving so it should have friction

B and C