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gneill
gneill is offline
#11
Mar5-12, 09:09 AM
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Quote Quote by supernova1203 View Post
hm... we havent learned how to add/subtract vectors in our course yet...maybe we will later on (there are still 3 sections left to this unit)

Anyhow, is there any way you can show me how to do this, in plain english please? :)
A picture is worth a thousand words Here's an example showing two vectors A and B being added. Each vector is specified by its magnitude (length) and angle to a reference direction, usually the positive X-axis. Note that vector B has its tail end placed at the tip end of vector A so that whatever quantities are represented by A and B applied successively. In other words, they are summed.



The resultant vector is the 'result' of adding A and B. The component of the resultant along the X-axis is equal to the sum of the X-components of A and B. Similarly, the Y-axis component of the resultant is equal to the sum of the Y-components of A and B. Use whatever trigonometry methods you know to extract the individual components.

##R_x = A_x + B_x##

##R_y = A_y + B_y##

##R = \sqrt{R_x^2 + R_x^2}##

##\theta_R = atan \left(\frac{R_y}{R_x}\right)~~~## note: beware of quadrant placement when dealing with negative valued components!
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