Exam Krackers Physics 30 min in class exam #81

[jar152]

How much work is done to move a point charge (q) a
distance of x, at an angle of 30° to the lines of force of an
electric field (E)

A. qEx
B. qEx sin(30°)
C. qEx cos(30°)
·D. Zero

The answer says it's b which can't be true.
Work = Force x Displacement. The displacement here is xcos30. Force = Eq. Therefore, the answer should be C ??

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[Spectar]

How much work is done to move a point charge (q) a
distance of x, at an angle of 30° to the lines of force of an
electric field (E)

A. qEx
B. qEx sin(30°)
C. qEx cos(30°)
·D. Zero

The answer says it's b which can't be true.
Work = Force x Displacement. The displacement here is xcos30. Force = Eq. Therefore, the answer should be C ??

Yeah just checked my EK book, it's definitely cos.