ENGR 34 Chapter 2, Day 1 2D

1
ENGR 34 Chapter 2, Day 12D 3D Vectors

1. 2D Vector Conversion and Addition
2. Vectors on your Calculator
3. Vector addition practice
4. 3D Spherical to Cartesian

2
2D Coordinate Conversion
Approach 1 (manual) Keep angles between 0 and
90, sin for opposite, cos for adjacent, do
signs yourself.
Approach 2 (automatic) Use standard defined
angles, (from x axis counter-clockwise), input
into calculator.
3
Vector Addition, Component Approach

• Break each vector into components
• Add components
• Convert to polar?

4
Vector Addition, Triangle Approach

• Construct Parallelogram
• Apply trigonometry

5
R-P, P-R Calculator Hints

• Modes approx, degree, cylindrical
• Special characters
• Grab enter
• Show steps on HW Exams

6
Name Game

• To facilitate collaboration in all your shared
  classes

7
3D Spherical/Cartesian
Avoid equations (no clear trig standard) Keep
angles between 0 and 90, Do signs
yourself, Notice the pattern
Blue angle first Az A sinq Ah A
cosq Grey angle next Ax A cosq cosf Ay
A cosq sinf
8
2D 3D VectorsKey Ideas

• Become calculator experts
• Avoid extra trig steps (use unit vectors)
• Be able to derive spherical conversion