A 2 ways of getting the resultant vector A
f GRAPHICAL METHOD f
1. To add vector B to vector A, first draw A on a piece of graphing paperto some scale, such as 1 cm=1 m, and so that its direction is specifiedrelative a coordinate system.
2. Then draw vector B to the same scale with the tail of B starting at the tip of A.
3. Vector B must be drawn along the direction that makesthe proper angle relative vector A.
4. The resultant vector R = A + B is the vector drawn from the tail of A to the tip of B.
y COMPONENT METHOD y
1. Consider a vector A in a rectangular coordinate system. A can be expressed as the sum of two vectors: Ax, parallel to the x-axis; and Ay, parallel to the y-axis.
2. From the definitions of sine and cosine, we see thatcos = Ax / A and sin = Ay / A, so the components of A are Ax = A cosand Ay sin. These components form two sides of a right triangle havinga hypotenuse with magnitude A.
3. To solve for the angle , which is measured from the positive x-axis by convection, we can write it in a form: = tan-1 ( Ay / Ax )
' ' ' did you get that ' ' ' for me this lesson is difficult, it really rocks my mind.. =]
