Search found 27 matches

by jac50
Wed Apr 15, 2015 8:46 am UTC
Forum: Logic Puzzles
Topic: Cheryl's Birthday
Replies: 29
Views: 6737

Re: Cheryl's Birthday

A slight tangent to the original question, but I know that the problem is asking what Cheryl's birthday is based on you being an outside observer to the problem. I was wondering if there's a way to work out how Albert was able to know the date based on him knowing that Bernard now knows the date. An...
by jac50
Mon Feb 07, 2011 8:53 am UTC
Forum: Coding
Topic: C++ program won't loop
Replies: 10
Views: 1401

Re: C++ program won't loop

Ohh ok, I see. I can see how that would affect a larger program anyway.

Thanks for the clarification.
by jac50
Mon Feb 07, 2011 8:17 am UTC
Forum: Coding
Topic: C++ program won't loop
Replies: 10
Views: 1401

Re: C++ program won't loop

Also - once the loops are sorted, there will be an error with : for(i=0; i<=4; i++);{ float salePrice=0; float price=0; cout<<"Enter the sale price"<<endl; cin>>salePrice; cout<<"Enter retail price"<<endl; cin>>price; float perOff=((price/salePrice)-1)*100; discount[i]=perOff; } ...
by jac50
Fri Feb 04, 2011 6:15 pm UTC
Forum: Coding
Topic: LaTeX on Linux (CentOs)
Replies: 5
Views: 3767

Re: LaTeX on Linux (CentOs)

@ ++$_ - I originally was going to use Tex-Live (as original post states). For some reason I couldnt get it to work, but took other advice with TeTeX-LaTeX, and it seems to work so far so good. Thanks alot. That tutorial looks useful, so will take a look. Got quite a few books on it all, but as you ...
by jac50
Thu Feb 03, 2011 10:17 am UTC
Forum: Coding
Topic: LaTeX on Linux (CentOs)
Replies: 5
Views: 3767

LaTeX on Linux (CentOs)

Hi all, First off, apologies if this is the wrong section - I was split between this or Computer Science. Anyway, I have decided to get into TeX much more, to enable me to write my second semester uni reports. I am aiming to primarily use CentOs, so using LaTeX would be my best bet. I am currently l...
by jac50
Wed Dec 29, 2010 9:10 pm UTC
Forum: The Help Desk
Topic: Interesting Problem regarding BluRay Drive...
Replies: 4
Views: 732

Re: Interesting Problem regarding BluRay Drive...

After trying what keeperofdakeys said, it seems as though it wasn't that.

System Idle Process wasnt running, and there weren't any programs which seemed to cause the spike.

Completely stuck for ideas now :(
by jac50
Tue Dec 28, 2010 9:09 pm UTC
Forum: The Help Desk
Topic: Interesting Problem regarding BluRay Drive...
Replies: 4
Views: 732

Interesting Problem regarding BluRay Drive...

Hi, An interesting problem with my parents desktop. If i try and load any cd/dvd/blu-ray disc into the computer, the computer slows down a lot ;literally on the point of crashing. At certain points, any music will stutter for a bit, then continue as normal. Operating System is Windows 7. I have trie...
by jac50
Wed Dec 15, 2010 10:34 pm UTC
Forum: Coding
Topic: Similarities between C/C++ and Java
Replies: 24
Views: 5830

Similarities between C/C++ and Java

Hi, I have learnt C for about half a year now, and wanting to learn Java for a placement i am going on next year. After reading through a book I have found in the library, the syntax is very similar to C. Only differences i have found so far that it is OOP, and that declaring arrays are slightly dif...
by jac50
Wed Nov 10, 2010 8:56 am UTC
Forum: Coding
Topic: MatLab question!
Replies: 15
Views: 1686

Re: MatLab question!

I havent heard of a simple function in matlab to do that, but you could do it using a for loop. for j = 1:size(y) if y(j) == certain_value x_temp = x(j); break end Apologies for any syntax errors. Haven't used Matlab in quite a while, but that should work. I'm interested to see if there is a functio...
by jac50
Sat Sep 18, 2010 7:58 pm UTC
Forum: Science
Topic: public misconceptions
Replies: 1073
Views: 153080

Re: public misconceptions

not sure if its been mentioned before - but saying '20mg bandwidth' instead of something like "a data rate of 20mg". really annoying :(
by jac50
Mon Aug 02, 2010 5:50 am UTC
Forum: Mathematics
Topic: Factorials question
Replies: 30
Views: 3526

Re: Factorials question

There is also the integral form of a factorial. forgotten it off hand, but i know thats what i used to prove 0! = 1.
by jac50
Mon Jul 05, 2010 8:44 pm UTC
Forum: Science
Topic: [Physics] Speed of propagation of electrical field
Replies: 19
Views: 4617

Re: [Physics] Speed of propagation of electrical field

Signals through copper = 2/3 speed of light? you sure? Any other proof besides the capacitance effect? Any calculations ive done with copper cables ive assumed they travel at (or close to to make negligible difference) the speed of light. i know for certain for optical fibres its around 2/3 of speed...
by jac50
Wed Jun 09, 2010 12:15 pm UTC
Forum: Mathematics
Topic: Determinants
Replies: 17
Views: 2380

Re: Determinants

Yep, that is right. But remember that you can take any row or any column and take the determinant off that.

If that makes any sense, either someone else can explain it properly, or ill try and rephrase it.
by jac50
Fri May 28, 2010 8:20 am UTC
Forum: Mathematics
Topic: Differentiation capacitance formula
Replies: 17
Views: 5976

Re: Differentiation capacitance formula

Ah ok, glad that its sorted. Knew it couldnt be a differentiation problem anyway.
by jac50
Wed May 26, 2010 3:18 pm UTC
Forum: Mathematics
Topic: Differentiation capacitance formula
Replies: 17
Views: 5976

Re: Differentiation capacitance formula

It should be. Possibly the units, but i'm not sure. You could try plotting the graph of the differential, and read off for 6ms.
by jac50
Wed May 26, 2010 3:01 pm UTC
Forum: Mathematics
Topic: Differentiation capacitance formula
Replies: 17
Views: 5976

Re: Differentiation capacitance formula

@ Katsuki - almost. you need to multiply out the brackets, and then the exponentialt term has V as a coefficient as well.

My answer agrees with Talith, definitely cant see how the answer could be in that range.
by jac50
Wed May 26, 2010 2:20 pm UTC
Forum: Mathematics
Topic: Differentiation capacitance formula
Replies: 17
Views: 5976

Re: Differentiation capacitance formula

Ah no, i know exactly where ive gone wrong. didnt multiply out the brackets correclty :S

v = V(1-e^(-t/T))
v = V - Ve^(-t/T))
v' = 0 - Ve^(-t/T)(-1/T)
v' = (V/T) e^(-t/T)

Still dont get the answer though. Odd. See if any1 else can figure it out. It isnt hard though..

James
by jac50
Wed May 26, 2010 1:50 pm UTC
Forum: Mathematics
Topic: Differentiation capacitance formula
Replies: 17
Views: 5976

Re: Differentiation capacitance formula

What are the values of t, T, and V that you have? and im assuming the E is e (the natural number i think :S ) If it isnt, not too sure. I also assumed you were differentiating wrt t. I get the derivative of v to be : v' = 0 - (-1/T)* E^(-t/T) = (1/T) * E^(-t/T) Th...
by jac50
Wed May 26, 2010 8:46 am UTC
Forum: Mathematics
Topic: Self Teaching PDE's?
Replies: 5
Views: 1460

Re: Self Teaching PDE's?

Thats great. Cheers for the replies. I'll check them out in the library later today then.

Thanks again
James
by jac50
Mon May 24, 2010 9:39 pm UTC
Forum: Hardware
Topic: 3D printer thread!
Replies: 14
Views: 2306

Re: 3D printer thread!

Yea - i assume so. Will try and look up his site to see what sort of advances he's made. Printing a fully functional 3d printer would be another project in itself though. I'm assuming he's done what you mentioned SlyReaper (no idea why i thought your name was SkyReaper, but anyway), by having it ass...
by jac50
Mon May 24, 2010 9:36 pm UTC
Forum: Mathematics
Topic: Self Teaching PDE's?
Replies: 5
Views: 1460

Self Teaching PDE's?

Hi, Ive just finished the pure maths modules of my electronics course, and realised I dont do any PDE's. I assumed that they would have been useful later on, so planning to learn them by self teaching over summer. What books would you recommend for this? Essentially some info on the basics, numerica...
by jac50
Mon May 24, 2010 9:54 am UTC
Forum: Hardware
Topic: 3D printer thread!
Replies: 14
Views: 2306

Re: 3D printer thread!

@SkyReaper

Yea it was SkyReaper. As far as i know (speaking to students in the Bath Mech Eng Department), it seems as though its under development. The problem being is the printing of the electronic components. I will try and keep up with the project though, as it sounds a wicked idea.

James
by jac50
Thu Apr 01, 2010 8:58 am UTC
Forum: The Help Desk
Topic: Do I need an anti-static mat to safely install a processor?
Replies: 17
Views: 3931

Re: Do I need an anti-static mat to safely install a process

Keep in mind your resistance is variable depending on a lot of factors. This include sweating and how good the electrical contact is (more pressure = better contact). If your muscles get contracted by the current, you may not be able to let go of the wire. ] Isnt that last point only to do with DC ...
by jac50
Wed Mar 31, 2010 5:50 pm UTC
Forum: Science
Topic: [Physics] - Squint Circle Problems?
Replies: 3
Views: 1668

Re: [Physics] - Squint Circle Problems?

Ah ok, i understand your first argument.

Simple angular momentum/torque stuff really. T=Fr, T=i(alpha) etc, conservation of angular momentum. if it cant be worked out using simple stuff like this, i'll definitely try and look it up though.

Cheers for the quick reply.

James
by jac50
Wed Mar 31, 2010 1:43 pm UTC
Forum: Forum Games
Topic: Can you produce [X] in less than 15 seconds?
Replies: 7745
Views: 779172

Re: Can you produce [X] in less than 15 seconds?

sadly not - all my bits of uninstalled computer are at home :(

a money box?
by jac50
Wed Mar 31, 2010 1:24 pm UTC
Forum: Forum Games
Topic: Count to a Million
Replies: 96124
Views: 7727908

Re: Count to a Million

28334
by jac50
Wed Mar 31, 2010 12:54 pm UTC
Forum: Science
Topic: [Physics] - Squint Circle Problems?
Replies: 3
Views: 1668

[Physics] - Squint Circle Problems?

Hi, From learning about vertical circle problems (Conservation of Energy essentially) and the typical horizontal problems (central force etc), what confused me is what would happen if the problem was somewhere between these 2 cases. The conservation of energy principle couldnt be used as there was s...

Go to advanced search