OCR 21st Century Additional Science B6C6P6 Post-exam discussion

Yep, it was one question. It simply asked you to draw ONE reflection line with perpendicular lines on it (like the incidence line) but more spread out, however, some people in my year drew THREE lines on that on picture.
What did you draw? o.O

Yep, it was one question. It simply asked you to draw ONE reflection line with perpendicular lines on it (like the incidence line) but more spread out, however, some people in my year drew THREE lines on that on picture.
What did you draw? o.O

Did the three lines (on the reflected line) have to be more spread out? I didn't know that

I'm pretty sure they did, well, 99% sure or so. I always go with my gut instinct because from experience, EVERY SINGLE TIME I change an answer I end up getting it wrong and regretting changing it

QUOTE=InadequateJusticex;32376496]Oh lol I get it now. I drew one line but since I didn't have a ruler, it wasn't really neat. But I tried to draw it just like the wave before being reflected, but obviously in the right direction...like same angle and all. I didn't do perpendicular lines at all o_o And I did ---|---|---|--- like the line was. What about you? They had to be more spread out. Anyway I did them spread out just incase - it can't hurt, even if they didn't have to be spread out then they would just assume I drew 3 lines and give me the mark anyway.
What other question were there, I forgot like half the paper now... I think I dropped a MAX of about 7 marks but I doubt it - with dropping 7 marks, I'm counting that I got ZERO on the one that you spoke about earlier (purification) but I'm sure I got atleast 2, I explained the first 2 points and slightly the third one they wanted you to explain.

I'm pretty sure it doesn't have to be spread out. In the CGP revision guide, page 84, it says 'when a wave crosses a boundary between two substances, it changes speed', shown with the waves being spread out or closer together. However, that only applies to refraction. Reflection on the other hand, looking at the picture on the same page, is different. The waves do not need to be spread out at all, but rather the same format before the wave hits the boundary.

Yep, it was one question. It simply asked you to draw ONE reflection line with perpendicular lines on it (like the incidence line) but more spread out, however, some people in my year drew THREE lines on that on picture.
What did you draw? o.O

Looking at that page I'm starting to think I got it wrong now I'm glad it was only 1 mark though. I thought it was a nice exam overall anyway The only thing I hated was the chemistry section - most people in my class got the questions afterwards, but in the exam I had to stop and think for some of them lol. btw what did you put for the state symbols? Did you include any (aq)'s? Also, the one about Water --> Hydrogen + Oxygen, how did you balance it?

I put:
2(H2O) ---> 4H + O2
I think I may have got the wrong drift on that question, someone please confirm if it's right/wrong, thanks :]

it was 2h2o--> 2h2 + o2

http://www.school-for-champions.com/science/images/waveobstacle-reflection.gif

I found that on Google, that's pretty much what I did

Looking at that page I'm starting to think I got it wrong now I'm glad it was only 1 mark though. I thought it was a nice exam overall anyway The only thing I hated was the chemistry section - most people in my class got the questions afterwards, but in the exam I had to stop and think for some of them lol. btw what did you put for the state symbols? Did you include any (aq)'s? Also, the one about Water --> Hydrogen + Oxygen, how did you balance it?

I put:
2(H2O) ---> 4H + O2
I think I may have got the wrong drift on that question, someone please confirm if it's right/wrong, thanks :]

uh-ohh. is my one still right? I'm pretty sure I heard someone say the same one as me and many people didn't use "H2" but wrong 4H o.o
)
That's pretty annoying man, another 1 mark (or 2, how much was it worth?)

ty

yep, now I'm pretty sure I got it wrong. 1 mark, oh well. What if I drew the reflection line, the refraction line and the transmition line and then I drew 3 lines on all of them, would I get the mark? (I did this and then I crossed out the other 2 and left the reflection one which ahd spread out ones).

Looking at that page I'm starting to think I got it wrong now I'm glad it was only 1 mark though. I thought it was a nice exam overall anyway The only thing I hated was the chemistry section - most people in my class got the questions afterwards, but in the exam I had to stop and think for some of them lol. btw what did you put for the state symbols? Did you include any (aq)'s? Also, the one about Water --> Hydrogen + Oxygen, how did you balance it?

I put:
2(H2O) ---> 4H + O2
I think I may have got the wrong drift on that question, someone please confirm if it's right/wrong, thanks :]

As well, I accidently wrote the symbol equation and not the word equation for the Calcium one.
Dropped a mark there

It Was Just

H2O = H+ + OH-

It woz the neutralisation equation - thank god i checked that H20 was at the beginning!
Woo i'd have lost 2 marks for a simple mistake

Majid

oh my god, EVERY SINGLE PERSON IN MY YEAR DID THAT. and then they changed it hydrochloric acid + calcium carbonate ---> calcium chloride + carbon dioxide + water

right? o_o

EDIT: what did everyone put for state symbols?

What did everybody put for the question about the chemical transmitter?

I put E,D,C,A,B I Think

Majid

What did everybody put for the question about the chemical transmitter?

I put E,D,C,A,B I Think

Majid