Vector B is in the third quadrant, therefore its x and y components are negative. If B's direction is 246 (counter-clockwise from the positive x-axis) then which expression best describes B's x-component?
a)B cos(246)
b)B sin (66)
c)B sin (246)
d)B cos (66)
e)B tan (66)
f) B tan (246)
Vectors? I hate these things...just confusing, haha?
the x component of a vector is always calculated by it's size multiplied by the cosine of the angle between the positive x-axis and the vector (counter clockwise....)
so (a) is the right answer.
note that cos(246) is a negitive quantity so we don't have to worry about plus or minus sign...
Reply:B cos(246)
Reply:Letter (a). Of course, the answer is negative because
cos(246 degrees) is negative.
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment