AQA A2 COMP 3 Computing 2015 - Official Thread

Reply 320

StealthyNoodle4

Original post by EllaR97

Ahhh yes, I remember that now! Thanks :-)

You're more than welcome! Good Luck for tomorrow! :smile:

Reply 321

AnnieFraz

2

Can anyone explain the operating system on phones. It was a question on the june 2014 paper. Good luck for tomorrow everybody XD x

Posted from TSR Mobile

Reply 322

gyroscope

in case anyone needed the june 2014 paper...

AQA-COMP3-QP-Jun14.pdf500.0KB

Reply 323

Robbo54

2

Original post by AnnieFraz

Can anyone explain the operating system on phones. It was a question on the june 2014 paper. Good luck for tomorrow everybody XD x

Posted from TSR Mobile

I think it's a case of remembering the points in the mark scheme, perhaps making some colourful flashcards to help you remember the points.

A phone OS may have a sandbox to run guest programs in.
A phone OS is likely to have less RAM/slower processor
Need to support certain set of peripherals like a GPS/gyroscope
Probably going to have sophisticated power management software

Reply 324

Gigabit

14

Original post by EllaR97

I was doing the Jun11 paper and the question asked "what is the smallest positive that can berepresented using normalised floating point system."
I put 0.0000001 with exponent of 1000, but the markscheme says 0.1000000 with exponent of 1000 - anyone know why?

Wikibooks agrees with me :-S

Thanks in advance!
:-)

That's just what I put! It made sense in my head :frown:

Reply 325

Gigabit

14

June 2011 is a horrible paper!

Reply 326

aLeXaNdRa08

How much do we have to know about how Turing machines work?
All i know is the basic definition of a Turing machine and a UTM.

Reply 327

PythonGuy

1

Original post by aLeXaNdRa08

How much do we have to know about how Turing machines work?
All i know is the basic definition of a Turing machine and a UTM.

The majority of marks on Turing machines come from interpreting the logic of one, and writing out the movement and actions of the read and write head.

As far as definition and explanation questions go, you also need to know the significance of Turing machines to computing in general (both the standard ones and universal).

I have seen one other question regarding how a UTM can be likened to an interpreter.

Reply 328

aLeXaNdRa08

Original post by PythonGuy

The majority of marks on Turing machines come from interpreting the logic of one, and writing out the movement and actions of the read and write head.

As far as definition and explanation questions go, you also need to know the significance of Turing machines to computing in general (both the standard ones and universal).

I have seen one other question regarding how a UTM can be likened to an interpreter.

Ok well thats good then. I'm just hoping that they don't suddenly chuck a six-mark question at us, about exactly how a Turing machine works.

Reply 329

ToxicFlop

Are the get and post methods response or request?

Reply 330

TabbyGuy123

Anyone know the Big O complexity of the insertion sort?

Reply 331

username1050473

14

Original post by TabbyGuy123

Anyone know the Big O complexity of the insertion sort?

Big O is worst case, right? If so, it would be

O(n^2)

. Because the worst case would be if the list was the wrong way round, and each element had to compare to each element before (so n-1 + n-2 + n-3 + ... + 1), which would sum to

\frac{1}{2}n(n+1) -1

.

Reply 332

AnnieFraz

2

What's a thick-client network please?

Reply 333

tommo97

1

Just remember 1st = Atomic Data, 2nd = No partial Dependancies, and 3rd = No Non key attributes!

Sort of in order of importance?
For 3NF there's also the court based rhyme of "Each attribute must represent a fact about the key, the whole key, and nothing but the key, so help me Codd!" (Codd was some database computer-y guy, you don't need to know anything about him for the exam but the rhyme might help!