The Dot Product and its Useful Properties

In this video I review the dot product formulas and its useful properties such as finding the angle between vectors and calculating work done on an object by a constant force. The dot product is the multiplication and addition of corresponding components of two vectors, producing a scalar. This result is also equal to the cosine of the angle between the vectors multiplied by their lengths. When the dot product is zero, the two vectors are perpendicular. Another useful property of the dot product is in projecting a vector onto another, which is useful in physics as a means of calculating work done by a constant force at a constant angle. There are many other applications of the dot product in physics, computer graphics, engineering, and machine learning. In fact, the dot product is fundamental in neural networks for measuring similarity between vectors.

Timestamps:

Question 5: Dot product: 0:00
- Solution: Dot product from lengths and angle between vectors: 0:12
- Dot product from vector components: 1:19
Question 6: Useful properties of dot products: 1:58
- Determining angle between 2 vectors: 2:09
- 2 vectors are orthogonal (perpendicular) if their dot product is zero: 3:03
- Projecting one vector onto another: 5:07
- Calculating work done by a constant force: 7:34
- Properties taken from ChatGPT: https://chatgpt.com/share/6e3be6a9-38d1-4ae7-852a-62977b6a492f: 9:21