Answer:
(a) theta = arctan (Ay/Ax) = arc tan (11/11) = 45°
(b) theta = arctan (Ay/Ax) = arc tan (11/19) = 30.07°
(c) theta = arctan (Ay/Ax) = arc tan (19/11) = 59.93°
To find the angle a vector makes with the positive axis, one needs to know the components of the given vector. Then the arctan of the ratio of the component of the vector along the y-axis and the component along the x-axis is computed. This gives the angle the vector makes with the positive x-axis.
Step-by-step explanation:
This angle is always measured from the positive x-axis in a counter clockwise direction towards the positive y-axis. The values of theta range from 0 - 360°.
The component vectors Ay and Ax are simply representing of the vector A along the respective axis. In terms of force, they represent the effect that force will have along the x- and y-axis respectfully. Mathematically they can be calculated using the formulas
Ax = Acos(theta)
Ay = Asin(theta)
Where theta is measured from the positive X-axis counter clock wisely
A = magnitude of the vector A and mathematically
A = squareroot(Ay² + Ax²)