Need help with physics magnitude and displacement

1. Jun 5, 2015

squareone

1. A car is driven 80 km west and then 30 km 45 degrees south of west. What is the displacement of the car from the point of origin? (magnitude and displacement)

2. A delivery truck travels 18 blocks north, 10 blocks east, and then 20 blocks south. What is the trucks final displacement from its starting point? Assume the blocks are all equal length.

Also help with: Given the following two vectors, where Vector A is 6.3 meters and Vector B is 3.5 meters: Determine the magnitude of the following vector sums:

a. A+B
b. A-B
c. B-A

I don't know where to start. Every example i looked at didn't help me solve these and they seem to contradict each other. I'm just starting in physics and deeply confused. Please help...

Last edited by a moderator: Jun 5, 2015
2. Jun 5, 2015

SteamKing

Staff Emeritus
Have you studied vectors at all? Do you know how to add two vectors together? Subtract them?

Hint: Rather than throwing a bunch of the same kind of problems into one thread, it is preferred that you post a single problem in a single thread. That way, replies can be concise and to the point.

3. Jun 5, 2015

squareone

I'm taking this class over the summer and no i don't know anything about physics. Its been 5 years since i took Algebra

4. Jun 5, 2015

SteamKing

Staff Emeritus
I'm not asking about physics. These problems are essentially math problems dealing with vectors. Do you know what a vector is?

5. Jun 5, 2015

CWatters

Try a diagram. Mark on it distances/length and angles. Complete any right angled triangles that spring to mind.

What branch of maths involves lengths, angles and triangles?

6. Jun 5, 2015

Staff: Mentor

Welcome to the PF.

Start with that question first. Draw a diagram of the 2 displacements, and use the Pythagorean Theorem to find the overall displacement vector...