Section 2-Algebraic Vector Addition-Part 1

The second way we’ll learn to add vectors is algebraically, of which the first part is breaking vectors into components.

Any given vector in two dimensions can be broken into a horizontal and vertical component. Read the section about using trigonometric functions to determine vector components on the following page: https://www.physicsclassroom.com/class/vectors/Lesson-1/Vector-Resolution

Remember when solving problems involving trigonometry with angles measured in degrees to set your calculator to degrees mode.

Practice Problems

For the below two practice problems, break each vector into its x and y components using sine and cosine functions, as explained in the link above. Round your answer to the nearest tenth (the first decimal place). It would be best to attempt these problems before our Zoom meeting for this section that way if you have any questions you can ask them during our meeting.

  1. 5 N @ 25° North of West
    • Answer: x = -2.1 N and y = 4.5 N (with up as my positive y direction and right as my positive x direction).
  2. 2 N @ 30° East of North
    • Answer: x = 1.0 N and y = 1.7 N (with up as my positive y direction and right as my positive x direction).

Assignment 2 – Due (Date filled in for actual course to meet the course timeline.)

Your assignment is to answer the following questions, which will be filled in on the multiple choice Google Form linked below. Please use up (North) as your positive y direction and right (East) as your positive x direction, rounding your answers to the nearest tenth (the first decimal place). Be sure to keep in mind which direction your components are facing and whether they will be negative or positive based on that direction.

  1. 12 m/s @ 45° North of East.
  2. 10 N @ 12° East of North.
  3. 5 N @ 30° South of West.

To complete your assignment use the following Google Form, making sure to fill in your full name and each answer. https://forms.gle/sqi13B3S1LpLU9NA6

Your assignment will be automatically marked upon completion so that you can review your answers. If you have any questions, do not hesitate to contact me.


Once you’ve completed all the tasks and learning for this section, please select an option on the Poll.ly form below to let me know how you’re feeling about your understanding of this section. You can cast your vote by clicking the icon beside the answer you want to pick.

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