Help - Vector Addition: Three Vectors

The Applet lets you construct the sum of three vectors of your choice, by either the Tip-to-Tail or the Parallelogram Method, and provides the answer; accompanying text provides a guide

Click on a number to view the explanation of the corresponding item.

  1. Vector Tool

    2. To draw a vector, select the Vector tool ; then click in the applet window and draw with the mouse. You can change the vector by dragging either its tail or its tip. You can move the vector without changing it by clicking it somewhere near its middle and dragging it.

    To draw another vector, repeat the procedure, beginning with the selection of the Vector tool.

  2. Dotted Line Tool

    3. To draw a dotted line, select the Dotted-Line tool ; then click in the applet window and draw with the mouse.

    You can change a dotted line by dragging either its tail or its tip. You can move the line without changing it by clicking it somewhere near its middle and dragging it.

    The Dotted-Line tool does not become active until Page 3 when you are asked to draw the resultant of the three vectors. The tool can help you in using the parallegram method. In the example construction illustrated in the figure at the top, dotted lines are drawn to construct the intermediate resultant (in black) of vectors and .

  3. Delete Tool

    4. You can delete any vector or dotted line that you have drawn by selecting the Delete tool and then clicking on the vector or dotted line.

  4. Intermediate Resultant

    5. On Page 3, you are asked to construct the resultant of the three vectors. This will require constructing the resultant of two of the three vectors before adding the third vector.

    In the example construction shown in the figure at the top, the resultant of vectors and is shown in black. Use the Vector tool to draw this vector. It will be drawn in blue at first. Then, when you draw the overall resultant, by again using the Vector tool, the intermediate resultant will turn black and the true resultant will be in blue.

  5. Overall Resultant

    6. The correct resultant vector will be drawn automatically (in green) when you go to Page 4. The program will let you advance to Page 4 only after you have drawn your resultant (in blue) on Page 3 by means of the vector tool.

    You can drag either the green or the blue resultant vectors by clicking on them somewhere near their midpoints and then dragging them.