We then went over two topics - one connected to yesterday's video that mentioned the dot product between two vectors, and the other related to graphing. The dot product that we saw yesterday provides a way to calculate the component of the force in the direction of motion when we calculate work, and today we saw the equation we should use - W = F x cos(theta) x d, where F is force, d is the distance over which the force acts, and theta is the angle between the applied force and the direction of motion. Here's the equation clipped from the online notes:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEiJ0uoQrEiNV3WUnUOqrTpJ2ki82PSERUHQz7YCwwmKOc8oUxtQBFd5lGEaJEi9ZIiqAHjQEoQ6NV5PtVq6tjAKt32GHOUZCm25VMi1cgwFOz6VTF2174UB7QYH620qOhF3Kd8NPdCLT3U5/s320/Picture1.png)
![](file:///C:/DOCUME%7E1/Larry/LOCALS%7E1/Temp/moz-screenshot-1.jpg)
We worked through an example of this and then we discussed the idea of graphing force versus distance and how the area under that curve becomes the work done, shown below:
![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEizbC2hEswIpPv_nNkP6qabpD4KOzJVRvbFdSzqQhq-ar7WBKqEmbrxdCfT_Tqg_Co6CIfZ0Ig0vXA_Oy9vJIyonIURx_Y88mX0FsZSwc9RGDWURrRN6rQTVJoZN6zoBh256pdutkKoMZlq/s200/Picture2.png)
We did a few examples of calculating KE, and then finished up with a review of the weekend blog assignment, which is to read the existing posts on our "Home Base" blog, and the model post you are now reading, and leave a "thoughtful" comment on one of them. Monday we will start writing scribe posts for real.