Biology; Chemistry; Physics: Post your doubts here!

[robinhoodmustafa]

well, curves are there check last questions of each paper, even in the mark scheme the term curves is used, so why do you thing these are straight lines!?

Check the paper before 2012..like 2011 and 2011. We are asked to plot a straight line but i would say the drawing graph part is only of 2-3 marks. Hand joined is accepted usually .

 

[Sparky123]

but curve is usually not smooth and takes time

 

[Sparky123]

Check the paper before 2012..like 2011 and 2011. We are asked to plot a straight line but i would say the drawing graph part is only of 2-3 marks. Hand joined is accepted usually .

a curve may come this session, so?.........

 

[Hasan Asim]

how does the mcqs answer sheet look like

 

[TheStallion-Reborn]

Any of you people know, about the allowance of 'flexicurves' in the science papers, like it is allowed in maths d?

dude, whts a flexi curve?

 

[robinhoodmustafa]

dude, whts a flexi curve?

www.ryman.co.uk/1342768199/Helix-Flexi-Curve-Ruler/Product

 

[robinhoodmustafa]

how does the mcqs answer sheet look like

something like this.. not exact

 

[TheStallion-Reborn]

www.ryman.co.uk/1342768199/Helix-Flexi-Curve-Ruler/Product

dis was a stationary thing aniways, is it the graph which doesnt necessarily have to be the perfect straight line or the perfect curve. right?

 

[robinhoodmustafa]

dis was a stationary thing aniways, is it the graph which doesnt necessarily have to be the perfect straight line or the perfect curve. right?

Well The curve should be smooth

 

[Muhammad Ali Khan]

https://www.xtremepapers.com/community/threads/o-level-notes-center.11138/ check here

ok i'll like your reply

 

[Khadija_1234]

Hi I need help with bio Oct/Nov 2012 paper 22 Q4 b part

 

[robinhoodmustafa]

Help me!

 

[Galaxy]

Help me!

Blood goes to his legs from the arties in high pressure but since its in low pressure in the veins and also cos his body is in a raised postion it slows down and much of it isnt pushed towards the heart and his weight of the blood in his legs causes the chair to fall. someone correct me if i'm wrong.

 

[TheStallion-Reborn]

Help me!

the blood vessels in the legs have very small amount of blood pressure. their flow back towards the heart is aided by the muscle contraction in legs. after a while, the blood keeps on accumiliating inside the legs but doesn't flow back out because there are no contractions to force the blood. Thus the accumulation of blood in the legs will add weight

 

[Sparky123]

Has any of you persons done an experiment as a means of demonstrating 'refraction' of sound!!!???

 

[nidz]

Hey can someone pls ans my question.
This is about the enrgy profile diagram of endothermic reactions in Chemistry. I dunno which one of them is correct :/
I have found both fo them in different book :s

http://www.google.com.pk/imgres?q=e...nh=179&tbnw=254&start=20&ndsp=12&tx=169&ty=63


Or


http://www.google.com.pk/imgres?q=e...bnh=187&tbnw=268&start=8&ndsp=12&tx=171&ty=53

 

[Kamihus]

Hey can someone pls ans my question.
This is about the enrgy profile diagram of endothermic reactions in Chemistry. I dunno which one of them is correct :/
I have found both fo them in different book :s

http://www.google.com.pk/imgres?q=energy change diagram for endothermic&hl=en&sa=X&rlz=1G1LENN_EN-GBPK532&biw=1092&bih=533&tbm=isch&tbnid=FS-EzL2V1b_4yM:&imgrefurl=http://www.science-scholars.com/chemtopic5studyguide.htm&docid=f41aGAon_lXQ5M&imgurl=http://www.science-scholars.com//chem%2520sl/exoea.gif&w=318&h=224&ei=uPdjUZyJKMHVrQfMzICYCw&zoom=1&ved=1t:3588,r:29,s:0,i:175&iact=rc&dur=2310&page=3&tbnh=179&tbnw=254&start=20&ndsp=12&tx=169&ty=63


Or


http://www.google.com.pk/imgres?q=energy change diagram for endothermic&hl=en&sa=X&rlz=1G1LENN_EN-GBPK532&biw=1092&bih=533&tbm=isch&tbnid=PzwYrrbI14FH2M:&imgrefurl=http://learnthings.co.za/content/secondary/Home/Lessons/Science/Chemistry/Grade12/physic_00/chemic_01/enthal_00/reacti_00/default.htm&docid=d3xA0ipLFCcIwM&imgurl=http://learnthings.co.za/content/secondary/Home/Lessons/Science/Chemistry/Grade12/physic_00/chemic_01/enthal_00/reacti_00/diagram7.gif&w=479&h=336&ei=uPdjUZyJKMHVrQfMzICYCw&zoom=1&ved=1t:3588,r:12,s:0,i:115&iact=rc&dur=593&page=2&tbnh=187&tbnw=268&start=8&ndsp=12&tx=171&ty=53

The second one is correct as the activation energy is the difference between the maximum energy in the reaction and the energy of the products.

 

[robinhoodmustafa]

Hey can someone pls ans my question.
This is about the enrgy profile diagram of endothermic reactions in Chemistry. I dunno which one of them is correct :/
I have found both fo them in different book :s

this one is correct.

 

[Sparky123]

Has any of you persons learned or done an experiment as a means of demonstrating 'refraction' of sound!!!???

 

[robinhoodmustafa]

Has any of you persons learned or done an experiment as a means of demonstrating 'refraction' of sound!!!???

we have done refraction of light.. No Sound!