Question

If v =5.00 meters/second and makes an angle of 60 with the negative direction of the y-axis coalculate the possible values of vx

Answer 1

An angle of 60 degrees with the negative y-axis could mean 60 degrees clockwise or counterclockwise, which translates to two possible angles (starting from the positive x-axis and moving counterclockwise) of 210 degrees or 330 degrees.

Then the horizontal component $v_x$ of a velocity vector $\mathbf v$ with magnitude $5.00\,\dfrac{\mathrm m}{\mathrm s}$ could be one of two expressions:

$v_x=\left(5.00\,\dfrac{\mathrm m}{\mathrm s}\right)\cos210^\circ=-4.33\,\dfrac{\mathrm m}{\mathrm s}$

$v_x=\left(5.00\,\dfrac{\mathrm m}{\mathrm s}\right)\cos330^\circ=4.33\,\dfrac{\mathrm m}{\mathrm s}$