# Problem involving Moore's Law

1. Feb 26, 2015

### TheQuizmaster

• Thread originally posted in a non-homework section, so missing the homework template
[Mentor note: Thread title changed to reflect problem content]

I have a problem that I would like to solve with Python, but I don't know the equation for this, here it is:

It has been shown that Moore's law not only applies to semiconductor density, but it also predicts the increase in (reasonable) simulation sizes, and the reduction in computational simulation run-times. First show for a fluid mechanics simulation that takes 4 hours to run on a machine today, that it should only take 1 hour to run on machines built 3 years from now, and only 15 minutes on machines built 6 years from now. Then show that for a large simulation that has an estimated run-time of 5 years that it would complete sooner if we waited 3 years to start the simulation.

What is the formula I would use to solve this?

Last edited by a moderator: Feb 26, 2015
2. Feb 26, 2015

### Staff: Mentor

A better question is "What is Moore's Law?" Have you done any research on the statement of this law?

3. Feb 26, 2015

### TheQuizmaster

I know that formula is expressed as Pn = Po x 2^n, the only thing I can surmise is that n = 3 / 2 = 1.5 for 3 years, 6 years would n = 6 /2 = 3, but that's all, how do I translate the rest, like how it should only take 1 hour on one and 15 minutes on the other, or for a large simulation with an estimated run-time, how do I work that into the Moore's Law formula?

4. Feb 26, 2015

### Staff: Mentor

No. According to Wikipedia,
Your formula doesn't take into account that the doubling occurs every two years.

Last edited: Feb 27, 2015
5. Feb 26, 2015

### TheQuizmaster

Guess I shouldn't trust this source then http://www.umsl.edu/~abdcf/Cs4890/link1.html [Broken]
That is why I'm here, so I can learn how to do these kinds of problems, what is the correct way to do it?

Last edited by a moderator: May 7, 2017
6. Feb 27, 2015

### Staff: Mentor

That article states:

Equation: Pn = Po x 2^n
[....]
n = number of years to develop a new microprocessor divided by 2 (ie. every two years)

Last edited by a moderator: May 7, 2017
7. Feb 27, 2015

### TheQuizmaster

Right, so it isn't suitable for the one I'm trying to solve, how would you go about solving this?

8. Feb 27, 2015

### Staff: Mentor

Adjust the formula so that you get doubling every two years instead of each year. It's not a big change. It shouldn't be too hard for a quizmaster...

9. Feb 27, 2015

### TheQuizmaster

I'm not that good yet, how would I adjust that, I want to learn how to solve this, but I don't know how?

Last edited: Feb 27, 2015
10. Feb 27, 2015

### Staff: Mentor

If you wanted doubling every six months (half a year), it would be $2^{2n}$. How could you change it so that the doubling occurs every two years?