##### Like what you saw?

##### Create FREE Account and:

- Watch all FREE content in 21 subjects(388 videos for 23 hours)
- FREE advice on how to get better grades at school from an expert
- Attend and watch FREE live webinar on useful topics

# Velocity Vectors

###### Matt Jones

###### Matt Jones

**M.Ed., George Washington University**

Dept. chair at a high school

Matt is currently the department chair at a high school in San Francisco. In his spare time, Matt enjoys spending time outdoors with his wife and two kids.

A **velocity vector** represents the rate of change of the position of an object. The magnitude of a **velocity vector** gives the speed of an object while the vector direction gives its direction. **Velocity vectors** can be added or subtracted according to the principles of vector addition.

Okay velocity vectors. Remember a vector is something that has both magnitude and direction okay so in this case I've got a vector going 4 meters per second East a velocity. Okay and I'm going to scale so that 40 centimeters is equivalent to 4 meters per second okay. Vectors can be added or subtracted and if it's in the same plane that's a pretty easy equation. Let's look at some examples, so I've got my 4 meters per second East and let's say I'm paddling in a canoe 4 meters per second okay and I'm paddling with the current and the current is 3 meters per second East. Well that's a pretty simple addition problem 4 meters per second East plus 3 meters per second East is 7 meters per second that's my total vector.

Okay it's also pretty easy if I have vectors going in opposite directions, I just subtract the second vector from the first. So I'm paddling now not down stream but I'm paddling up stream with the current going against me. So my 4 meters per second East is being countered by a vector that's going 3 meters per second West I'll try to be more accurate there and probably it would be right about there. So if I subtract 3 from 4 I get 1 meters per second East is my total vector. Okay, now those are pretty straight forward and sometimes you'll see problems like that but vectors often times are not moving either in the same direction or in the counter direction but they're often moving at right angles. So now let's take my canoe and now let's say I'm not going up or down the river but I'm going across the river. Okay and here I'm paddling my canoe 4 meters per second East but the river is flowing South and it's flowing 3 meters per second South.

Okay, well now when I add my vector I don't just get a smaller or larger vector I actually get a vector that at a different angle, at a different direction. So when I connect my 2 vectors I make a triangle okay and now to calculate this velocity I've got to do a little Math and since I have a right triangle I can look at these values. So I've got my this value and this value, if I have this value squared and this value squared it's going to equal this value squared. So let's go ahead and write that formula a squared plus b squared equals c squared and that's the value I want to find right there is c. Okay so if I go ahead and solve that I've got 4 squared is 16, 3 squared is 9 and that equals 25. Well 25, the square root of 25 is 5 so my new vector here is 5 meters per second South East and that's how you solve vector velocity problems.

Please enter your name.

Are you sure you want to delete this comment?

###### Matt Jones

M.Ed., George Washington University

Matt is very comfortable in front of the whiteboard and is able to make every topic easy for anyone to digest. His straightforward approach to teaching is very refreshing.

Great teaching, this is exactly the concept i was struggling over for my physics test tomorrow. Thank you!”

This video has a 99 percent probability of being the best video I've ever seen.”

Amazing !!!...I have not seen anybody explaining Quantum Physics so effortlessly......Probably you have understood it better than anybosy else.!!!...This is quite amazing...!!!..Keep up the good work....”

#### Related Topics

- Relativity in Motion 24,916 views
- Displacement 18,859 views
- Average Speed 16,696 views
- Speed-Instantaneous Speed 14,290 views
- Average Velocity 16,912 views
- Instantaneous Velocity 20,265 views
- Acceleration 17,986 views
- Free Fall 18,536 views
- Graphs of Motion 20,651 views
- Vector Direction 13,453 views
- Vector Quantities - Scalar Quantities 16,896 views
- Components of Vectors 12,938 views
- Projectile Motion 21,716 views
- Linear Motion 18,222 views
- Parabolic Motion 12,503 views

## Comments (0)

Please Sign in or Sign up to add your comment.

## ·

Delete