Download 111 Quizz 1 ``solve``

1)
2)
Since the charge object is electron so the force on it is opposite to the electric field
3)
F1=K q1 q2 / r2 = kq2/ 12
to the right
F2=K q1 q3 / r2 =k q2 /22
to the right
F = F1+F2 = 18 N
4)
What is the direction of the electric field of the charge distribution below at the points 1, 2, and 3?
(Note: points 1 and 2 are on the line bisecting the segment connecting the charges.)
5 ) Positive charge +Q is uniformly distributed on the upper half of a semicircular
insulating rod, and negative charge –Q is uniformly distributed on the lower half. The
direction of the electric field at point P, the center of curvature of the rod, is
a. Upward.
b. Downward.
c. Points to the left.
d. Points to the right.
e. Points diagonally upward.
The answer is (b)…
The field of the positive charges points away from the top half, while the field of the
negative charges points toward the bottom half; the horizontal components of the electric
field due to the two halves of the semicircle point on opposite directions and therefore
cancel, while the vertical components all point down and add.