OCR Gateway GCSE Physics B P4,P5,P6 (17th June 2015)

i don't think just filling in the table would get 4 marks because i'm sure i've seen similar logic gate questions for 2/3 marks.. but at the same time i don't know how much you'd be able to write for that 6 marker. IT WAS AWFUL. i left it right at the end and still didn't understand. i had to make up some random BS because i really didn't get it?? i just said if you get an output of 1, a segment(s) would become shaded and not if it was 0 haha.

the other six markers were good and overall it was an okay exam! some questions tripped me up but hopefully i did enough for A*. i think i got the first suvat question in p5 wrong because i didn't realise you had to change it to minutes. BUT did anyone get 4.0 for the deceleration ??

P5 -->

7 minutes to reach speed
ideas about resultant forces of gravity and forward motion
3.99m/s2
different ideas/ways of doing things/to verify EASY QUEstioN!
Use curved/parabolic shape to focus waves
move the dish to follow satellite
site the dish higher up to avoid interference
B is reflected it's below 30Mhz
C is scattered as it's above 30GHz
prism 6 marker --> light is a wave, waves refract in denser medium like glass, white light is refracted, different colours refracted more or less depending on WL, red has longest WL, refracts least, violet is shortest WL, refracts the most.

^^ there's many people who over exaggerate how supposedly good they did all I'm saying is you shouldn't get cocky as you may get an unwelcome surprise on results day.

This exam board is very ruthless this is why the GB are so low to compensate for the precision of answers required - for the time question did you guys get 5m? And for the deacceleration I just knew I messed it up. Regaring robot adv/disadvantages I said: Good - no pay, improves safety. Bad - takes job of workers, lack of reliability as it may need to be charged. I tried to find that hearing frequency question via trial and error but never had enough time.

I got an deceleration of -3.99m/^2


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Aaah the hearing frequency question confused me aswell and then I realized that
the overall average frequency was at the bottom of the table so I substituted each of the individual frequencies plus the unknown frequency into an equation and then made x the subject. Watch me still get the wrong answer though haha

I'm pretty sure a minus sign might lose you a mark.

The deceleration was in bold which makes me think they were looking for a positive value.

If they'd asked for acceleration a negative answer would be valid.

THe calculation is
v2 = u2 + 2as
120^2 = 2000 ^2 + 2x100000a
a = -3.99m/s2

Well deacceleration is Negative Acceleration - surely you have to put a negative sign in front in order to shows its negative acceleration?>

Yep but I think the question specifically asked for deceleration so a negative deceleration is an acceleration which would be wrong since it was slowing down.

How is the answer to the acceleration 3.99??

I have the paper, any questions?

It's quite wordy so I won't be able to post a full MS just yet.

Seems quite nice to me, okay 6 markers, lots of straight forward stuff, only a few random bits.

the question with what beta particles does, i put the elmenent gains a proton

Well deacceleration is Negative Acceleration - surely you have to put a negative sign in front in order to shows its negative acceleration?>

I think that's correct, it loses a neutron and gains a proton

im pretty sure neutrons stay the same.

Nope, its protons. +1 proton and -1 neutron when beta is emitted.

beta has 0 neutrons. It should be: atomic mass remains unchanged but atomic number increased

Look in the textbook
But yes, the atomic mass stays the same but the atomic number does increase!

exactly... the atomic number is protons not neutrons