I'M DEAD... well close to it.

[Galleria]

Hi,
My IGCSE exams are in less than a month and I'm giving Coordinated Science and I'm really not all that prepared. I have a few problems in Math as well but I have no problem in any of the others. I need to finish understanding everything by the 20th of October of these two subjects so that I can get A*'s in both. Our school's mock Math exam was ridiculous easy as out of 60, 35 got A* and that's the grade they're sending for the expected grade. By the way, can anyone tell me if IGCSE sends the percentage of scores too?
And, yes, anyway, I have a lot of problems in Math and Science that I need to clear out by the 20th. By Friday, I must finish with Physics (the part of Coordinated Science). These are my problems for Coordinated Science;
- Ionisation process of Hard Water
- Rocks... oil store in them.. and that millions of years fossil fuel thing
- Hooke's law (I did a test after studying myself and got 18/25 . I suck at it . lol)
- The lens stuff from Light
- Magnetism XX
- Radioactivity (well I haven't really studied so nvm this) XX
- Bone & Muscle
- Heart
- Ecology XX
- CRO (Cathode Ray Oscilloscope)
- Prisms & Parallel-sided block thing . I need to understand this for MCQ
- Ethene -> What is hydration, hydrogenation?
- Static Electricity ( I NEED SOME REAL HELP WITH THIS . FRICTION AND STUFF THAT HAPPENS  HERE)
- Plants XX
- Menstruation
- Glass, bonding (I don't understand Giant Molecular and the Metallic Bonding stuff)
- Haber Process, Contact Process, Ostwald Process XX
- REED SWITCHES ?
- Nuclear Fusion/Fission ?
- Constructing Keys for Bio Ecology
- Iron Extraction process XX
I have more but they are to be studied, not helped with.
lol , could someone explain a few of them to me ?
I really suck at the things I listed. Well not know anything, but I don't understand them well.

And for Maths :
- Vectors
- Transformation (I don't get a single thing. It takes me half an hour to do one question)
- Is there like a formula for symmetry ?
- How do I take out the Increase/Decrease Percentage?
- Probability
- Graphs
- Parabola
- Loci.

.
So that's about it .
could someone like help me with it bit by bit ? I really will be in trouble otherwiseee!

The ones that have "XX" don't need special attention . I just could use some resources for them though .

PLEAAAAAAAAASE HELP ME!!!

[elemis]

Read this first.

Hookes Law in short states that the EXTENSION of a spring is directly proportional to the load (in Newtons) extending it.


What lens stuff exactly ? Check THIS out.

For CRO.  http://www.doctronics.co.uk/scope.htm  READ BELOW TOOO !!!!

cathode ray oscillascope. has 6 parts.

the filament: it goes through thermionic emiision(where a substance is heated it releases electrons) this filament is heated and releases electorns with negative charge.

the anode grid: it has a positve charge. this controls the nrightness (ill tell u how later)

the cathode grid: it has a negative charge, this allows the beam of electron (the electrons emitted when tht filament was heated)

the y plates:hese have plates with (+) and (-) charge and are attached vertically to each other on the tube of the CRO. this helps the beam of electrons move up and down so the beam of electrons spread evenly (up and down) on the screen.

the x plate: these have plates with (+) and (-) charge and are attached horizontilly to each other on the tube of the CRO. these help the electrons move (left and right) as it hits the screen.

the screen: at the end of the CRO is the screen (made of fluroscent usually) when electorns hit this screen it glows.

without x plate and y plates u will see the beam of electrons hitting one point of the screen only (so only tht part glows) for eg:on TV (just an example) , if with out x plates and y plates, picture can only be seen as a spot of light (picture) on the screen. but with x and y plates the electrons are able to reach both (up and down) and (right and left) with the help of y plates and x plates respectively. (ill tell u how they work later))

how does the OCR work?
first the filament is heated, beams of electrons are emitted (this is callerd thermionic emission). they go throu the cathode. what does cathod do? Cathode are negatively charge (-) and so are the beam of electrons, so repulsion take place due to similar charges allowing some beams of electrons to "stay back". This control the brightness cuz "the more number of electrons hittin the screen, the brighter the pic comes on the screen". ok, then the beams pass through the anode. what does the anode do? Anode is positively charged (+) and the beam of electrons are oppesitely charged. this anode atracts the beam of electron giving the "boost" or "acceleration" and to travel in a straight line (beam). then it reaches the Y plates. as i told u the help the electrons move up and down . they are plates with voltages (charged with (+) and (-))). they are  GIVEN WITH A.C VLTAGE because if it was D.C then the elctrons would only move up OR down depending on the position of the positively charged plate ( as beam of electron is negatively charged). u see, A.C current changes its direction so the plates change their charges, whic means (+) become (-) then later (-) becomes (+). so (+) charge changes its positon and so does the beam of electron which changes its direction of deflection. this helps the electrons to touch both up and down of the screen.

the X plate are same, except they help the electrons to move right and left they are also charged except tht they are aranged horizontally. they are time base. the work with time, how? by letting the voltage between these plates go 0 then after sometime go to a certain value. how tghis helps? as the voltage has acertain value thts not 0 the beam deflects to towards positively charged plate. then when after a certain time it the voltage goes 0 immediately. this all ows the beam of electrons to GO BACK its old path (which was before deflection at X PLATE), then vise versa. this helps the electrons go left and right on the screen.

U might ask what in x plate there is time base and in y plates are AC current? why cant the put AC on the xplates too? This is because i think tht the time base system helps beam to go in the REQUIRED or aprropriate horizontal path.

then finally the electrons reaches the screen in every direction (with the help of x and y plates) which causes the whole fluroscent screen to glow or lit.

[elemis]

For Metallic Bonding memorise this definition for full marks:

It involves a lattice of positive ions surrounded by a sea of negative electrons. The electrons are mobile. There are strong electrostatic forces between the ions and electrons.

Macromolecules are giant covalent structures e.g. Diamond.

Hydration

Is where an Alkene is reacted with STEAM to turn it into an alcohol.

You need Phosphoric acid catalyst, 300 centigrade and 60 ATM for this reaction.

Hydrogenation

Is basically adding hydrogen to an alkene, forms an alkane. You need a nickel catalyst and 150degrees for this reaction.

[elemis]

For ALL the IGCSE Chemistry reactions and the conditions required see this : https://studentforums.biz/references-and-resources/chemistry-guide-a-guide-to-special-conditions-needed-for-various-reactions/

I dont do Biology, but this is an awesome site for any bio topics http://www.biology-questions-and-answers.com/index.html

[elemis]

For the prisms and parallel sided blocks thingy :



For the prism notice how the light bends when hits the prism the first time and then DIFFRACTS. Once the coloured spectrum reaches the second prism surface it BENDS DOWNWARDS again.

[elemis]

For percentage decrease or increase

Use the formula : original amount - new amount
                                    original amount                 * 100    

What graphs do you have an issue with ?

What do you not understand in probability ?

For Loci read the two scanned pages below

[elemis]

Static Electricity : http://www.s-cool.co.uk/gcse/physics/static-and-current-electricity/static-electricity.html

Reed Switch : is basically two wires passing through a glass bulb. Around the bulb is a wire.

When an electric current passes through the wire around the bulb a magnetic field is induced that magnetises the two wires in the bulb.

The wires in the bulb become opposite poles, attract each other and close to complete a circuit.

The wires in the bulb are normally separated and NOT touching. They only come into contact when magnetised.

[Galleria]

OH MY GOSSSSSSSSSSSSSSSSSSSSSH!
THANK YOU SO MUCH !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
:O :O :O :O !!!!!!!!!!!!
GO ARIIIIIIIIIIIIIIIIIIIIIIIIII!

[elemis]

OH MY GOSSSSSSSSSSSSSSSSSSSSSH!
THANK YOU SO MUCH !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
:O :O :O :O !!!!!!!!!!!!
GO ARIIIIIIIIIIIIIIIIIIIIIIIIII!

No worries.

I've modified my previous posts - some pictures have been added and I added some scans regarding Locus.

So refresh this page from time to time and check each post to ensure you've not missed anything new. I'll be adding new stuff all the time.

[Galleria]

Graphs - I need to learn all the general stuff . lol

[elemis]

Graphs - I need to learn all the general stuff . lol

You're not being very specific. Do you need stuff regarding histograms or CF graphs ?

[Galleria]

CF Graphs . lol

[elemis]

CF Graphs . lol

And what is it you dont understand in CF graphs ? Please, be specific. I dont have the whole night to waste typing stuff for you.

[Galleria]

OMG . don't get angry . don't botheeeer . this is enough .

[Arthur Bon Zavi]

By the way, can anyone tell me if IGCSE sends the percentage of scores too?

For your information, I m from India and, I got the % mark sheet!
Don't know about the other zones.