Q&A - P5 Science

[janice_0950]

Kangkangteo:

janice_0950:

Hi all Science expert!


http://s256.photobucket.com/user/disneyterris/media/11-2.jpg.html

(answer sheet shown is No. 2 (A & D) why?

Answer is (2) - A and D.

When the cap is removed, the water from the container rushes into the bottle to displace the air in the bottle, so the air rushes out of the bottle and appears as bubbles moving up the surface of the water.

Note: Basically the water rushes into the bottle because its pressure is higher than the pressure of the air in the bottle.

Thank you, Kangkangteo :rahrah:

[janice_0950]

Hihi All Science Prof,


Qn: 3
http://s256.photobucket.com/user/disneyterris/media/1-3.jpg.html

Qn: 22
http://s256.photobucket.com/user/disneyterris/media/2_1-1.jpg.html

Qn:42
http://s256.photobucket.com/user/disneyterris/media/3_a.jpg.html

please kindly help to explain above those questions. OMG! It is killing me......:( Sad to said......

Please kindly help.....Thank you in advance!

[HFPMAT]

janice_0950:

Hihi All Science Prof,


Qn: 3
http://s256.photobucket.com/user/disneyterris/media/1-3.jpg.html

Qn: 22
http://s256.photobucket.com/user/disneyterris/media/2_1-1.jpg.html

Qn:42
http://s256.photobucket.com/user/disneyterris/media/3_a.jpg.html

please kindly help to explain above those questions. OMG! It is killing me......:( Sad to said......

Please kindly help.....Thank you in advance!

First question 42,
I find answers in green wrong.
Even question asked in (b) is not correct. It should be asked as \" what is the relationship between size of the steel sphere and heat energy they contain after heating at same temperature?\"
temperature is defined as average kinetic energy of given object
while heat energy is defined as total kinetic energy of given object.

so ans (b) as the size of steel sphere increases, heat energy it contain will increase.

(c) It is because bigger sphere will have more molecules at higher temperature than smaller sphere.



Q 22, ans (2)
Ice cubes will melt faster than block of ice because ice cubes have more exposed surface area to gain heat than block of ice.


Q (8), ans (3) asexually produced offspring will be exactly same as parent. while sexually produced offspring will have characteristics inherited from both parents.
plant Q is exactly same as parent plant Z. So it is more likely to be produced asexually. while plant P must have inherited colour and size from other parent, so must be produced by sexual reproduction.

[jacsplace]

Hi,

Would like to enrol dd in science revision classes this year-end school hols. Anyone got any recommendations? Something along or near NEL stations would be good. Not too complicated a route as FDW will probably have to be the one to take her there and back.
TIA!

[yorky_plume.016347yahoo.016347com.016347sg]

hi,


im puzzled why the answer was incorrect?


http://i58.tinypic.com/2nswb3a.jpg

thanks
AT

[HFPMAT]

AT:

hi,


im puzzled why the answer was incorrect?


http://i58.tinypic.com/2nswb3a.jpg

thanks
AT

Plant cell can be identified by presence of chloroplast and cell wall.
Answer should be no. 3 only.

[angel]

can water which is freezed in the fridge falls below 0 degrees?


A graph shows water (A) at 30 degrees, took 15 mins to turn to 0 degrees (B), stayed at 0 degrees for 15 mins and dropped to -10 degrees after 10 mins (D) and stayed -10 degrees for next 15 mins (E).
(x-axis is TIME and y-axis is TEMP)
(A) 0/30, (B) 15/0, 30/0, (D) 40/-10 & (E) 60/-10

Qn asked :
1)What was the temperature of the freezer compartment?

2) Explain what happened to the beaker of water from B to C.

3) Which part of graph shows cooling of water to freezing point of water?


Is the ans
(1) -10 degrees
(2) The water freezed at 0 degrees at (B) and stayed for 15 mins at 0 degrees.
(3) Part A to B.

Anyone can help?

[dioprem]

angel:

can water which is freezed in the fridge falls below 0 degrees?


A graph shows water (A) at 30 degrees, took 15 mins to turn to 0 degrees (B), stayed at 0 degrees for 15 mins (C) and dropped to -10 degrees after 10 mins (D) and stayed -10 degrees for next 15 mins (E).
(x-axis is TIME and y-axis is TEMP)
(A) 0/30, (B) 15/0, (C) 30/0, (D) 40/-10 & (E) 60/-10

Qn asked :
1)What was the temperature of the freezer compartment?

2) Explain what happened to the beaker of water from B to C.

3) Which part of graph shows cooling of water to freezing point of water?


Is the ans
(1) -10 degrees
(2) The water freezed at 0 degrees at (B) and stayed for 15 mins at 0 degrees.
(3) Part A to B.

Anyone can help?

Assuming that the water is pure, water in the liquid state can never fall below 0 degrees, as that is the freezing point of water. Once the water has frozen, its temperature can continue to decrease, till it reaches the temperature of its surroundings.

And the answers you have given are all correct.

Hope this helps!

[Blue Pearl]

Not easy Science.

[fiona2004]

Can anybody help to look at the following question? It is one of CA1 from MGS. Thanks a lot.