**Here are some google glasses that actually look cool.**

**Here’s what Google Glasses can do.**

**Instead of using the Google Maps on your phone the Google Glasses put the map onto the glass lense so you can see where to go and where you are going. Theoretically.**

**…………………………………………………………………………………………………………..**

# The Maths

**Google Maps uses GPS or Global Positioning System satellites and simple maths of TRIANGULATION or, in the case of the 3D model, 3D TRILATERATION to accurately locate your position on earth.**

**………………………………………………………………………………………………………….**

**You will find excellent explanations of how GPS works at the Nova Scotia Dept of Education website and by **Diana Cooksey
MSU GPS Laboratory website.

**………………………………………………………………………………………………………….**

**Simple Explanation: **

**GPS satellites broadcast two signals which allows the GPS program in your phone or device to calculate your distance from the satellite. GPS needs data from 3 satellites to locate your position on earth.**

**………………………………………………………………………………………………………….**

**2D Model: **

**Let’s assume your phone can calculate how far you are from a radio tower. **

**Tower 1: **

**Your phone can calculate how far your are from the tower but you could be anywhere on the first circle.**

## ……………………………………………………..

**Tower 1& 2: **

**Your phone can calculate your distance from two towers and locate you at one of two points where the circles intersect. **

## ……………………………………………………….

**Tower 1, 2 & 3: **

**Now you phone can accurately find your position at the intersection of 3 circles.**

**………………………………………………………………………………………………………….**

**3D Model: **

**Your phone can calculate how far you are from a satellite.**

## ……………………………………………………………

**Satellite 1: **

**You could be anywhere on the first sphere.**

## ……………………………………………………………

**Satellite 1 & 2: **

**You could be anywhere at the intersection of the two spheres. These spheres intersect along a circle.**

## ……………………………………………………………

**Satellite 1, 2 & 3:**

** The 3rd sphere will cross that circle at 2 points. As one position is not on earth it can be discarded. **

**………………………………………………………………………………………………………….**

**Error Alert:**

**All measurements have an inbuilt uncertainty (scientists call it an error) because the accuracy of instruments is limited. Measuring across such long distances makes for significant errors. One problem for GPS is signal interference.**

**………………………………………………………………………………………………………….**

**………………………………………………………………………………………………………….**

**New Techno Frontiers in the Maths Classroom**

**………………………………………………………………………………………………………….**

**1. If you teach maths wearing Google glasses you can INSTANTLY record students bad behaviour in class on your computer. Wow! Evidence. THE FORCE BE WITH YOU, Mathspiggies.**

**OR**

**2. You can record a maths lesson using Google Glasses. It is already happening, my Sweeties. Have a look at this.**

** **