Quote:
Originally Posted by Yak
Your vectors can't be right, they're close(ish) but the inaccuracy may affect the result: most obviously 1^2 + 20^2 > 20^2
(jt20's were correct, but he mixed levels of accuracy, craig's were close, too, but zero is not probably not adequate) Math/physics/engineering rules - keep your accuracy (aka 'decimal places') consistent.
A= 28.68x + (-8.77)y
B= 1.04x + 19.97y
|A+B| = ((29.72x^2) + (11.20y^2))^-2 = 31.76
Theta = arctan 11.20/29.72 = 20.65 ccw from x.
The answer is fractions of a degree different from Craig's. How close do you need to be?
Cool java tool for visualizing here: http://www.surendranath.org/Applets/Math/VectorAddition/VectorAdditionApplet.html
Basic pic here: http://hyperphysics.phy-astr.gsu.edu/hbase/vect.html |
Everyone... "m" was for meters, ya know the SI unit for length
where did you get those different values from? I posted the values from the question I was given.. so confused now
I see what you did.. with the Ax^2 + By^2 to get the result.. Why did you use those two values?
I can figure out why you used those two values for the arctan calculation after I know why you selected those two.. Thanks for your help everyone