I saw a post on reddit asking whether imaginary numbers were actually any use at all.
My response was getting so long, I decided to post it here:
Author: Dr Mike
Solar Powered Saffron Rice
[This is a back-issue of one of this site’s newsletters]
We got solar panels installed about 6 months ago. I did the math, and figured they’d pay themselves off within 5-6 years. Your results may vary.
I’ve been tracking very carefully how much they generate. Watching the numbers tick over produces some strange ideas in me sometimes. For example, I started wondering – if all the energy from the panels were converted into saffron, how much saffron rice could I make?
Solar Powered Saffron
My solar panels have generated 1500 kWh of energy since they were installed 6 months ago.
Now, Einstein tells us that energy has mass. How heavy is 1500 kWh? We can use E = mc2 to find out.
Here, E is 1500 kWh, the speed of light c is 186000 miles/second. Unfortunately, we can’t just divide 1500 by the square of 186000. Sure, that would give the mass, but not in any unit I’m familiar with – when you tell me how much something weighs, I want to hear it in pounds, or kilograms, or ounces… even centiweight would do, if I have Google handy.
Continue reading Solar Powered Saffron
Monday Morning Math Gifts
[This is a back issue of one of this site’s newsletters]
Have you done all your Christmas shopping?
Sad News for Comet Watchers
[This is a back-issue of one of this site’s newsletters]
The ancient Greeks told a story about Icarus, who wanted to fly. He glued feathers to his arms with wax, and flew – but flew too close to the sun. The wax melted, the feathers dropped, and Icarus fell to his death.
Six months ago, we were told about a coming “Comet of the Century”, comet ISON. If things had played out differently, it might have been brighter than the full moon in the dawn skies around now.
Do You Know The Apple Man?
I was discussing some topic with a colleague, and he said “and what about the Apple Man?”
“The Apple Man?” I asked.
Apparently, in German (my colleague hails from Germany) Apple Man, or Apfelmännchen, is the word used for the Mandelbrot Set.
Do Your Kids Understand When You Say It’s Not Christmas Yet?
[This is a back issue of one of this site’s newsletters]
Christmas is around the corner!
If you have young kids at home, try setting up an Advent Calendar.
Continue reading Do Your Kids Understand When You Say It’s Not Christmas Yet?
Can You Solve This Puzzle?
I saw this puzzle the other day.
You have two fuses. Each fuse is a piece of string, that burns for exactly 1 minute. However, the fuse doesn’t burn evenly, so cutting the fuse in half doesn’t give you two 30 second fuses.
A Simpler Solution
[This is a back-issue of one of this site’s newsletters]
Last week, I emailed you a way to solve a simple math puzzle – how do you find a rectangle whose area equals its perimeter?
I took the puzzle, mixed in a little bit of algebra, and voila! A puzzle solution factory popped out, letting you generate rectangles from pythagorean triplets.
More On The Rectangle Puzzle
Last week, I posted a solution to a puzzle – how can you find a rectangle whose area equals its perimeter?
This week, I’ll post a simpler solution.