Three point charges q1, q2, and q3 are located at points (-3, 0), (0, 0), and (3, 0). The outer two are positive, while the one at the origin is negative. To calculate the electric force on another charge Q at point (0, 3), we need "r hat" vectors towards charge Q from the other three charges. Please find the three "r hat"'s.

Question

anonymous · Answer

r hat is the displacement vector. simply find their magnitudes and the unit vectors in the direction, r.
for example, (3,0) to (0,0) is,
$\vec r =|\vec r| \vec u_r$
$\vec r =\sqrt{3^2} (3\vec u_x)=9 \vec a_x$

anonymous · Answer

sorry, the last is $u_x$ not $a_x$