The position vector can be
transcribed as:
A = 6 i + y j
i points in the x-direction and j points
in the y-direction.
The magnitude of the
vector is its dot product with itself:
|A|2 = A·A
102 = (6 i +
y j)•(6 i+ y j)
Note that i•j = 0, and i•i = j•j =
1
100 = 36 + y2
64 = y2
get the square root of 64 = 8
The vertical component of the vector is 8 cm.
