Force on moving charge in ELECTRIC field

AI Thread Summary
The discussion centers on the behavior of a charged particle in a uniform electric field, specifically regarding the path it takes. The correct answer to the question posed is option D, which states that a negative charge traveling left to right in a downward-directed field will follow the described path. Participants clarify that while the electric field exerts a force on positive charges in the direction of the field, negative charges experience a force in the opposite direction, resulting in an upward force on the negative charge. The assumption that the particle enters the field at an angle is crucial to understanding its trajectory, as it initially moves downward before curving upward. This insight resolves confusion about the expected motion of the negative charge in the electric field.
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Homework Statement


The diagram shows the path of a charged particle through a uniform electric field, having vertical
field lines.

(the iamge has been attached)

What could give a path of this shape?
A a positive charge traveling left to right in a field directed downwards
B a positive charge traveling right to left in a field directed downwards
C a negative charge traveling right to left in a field directed upwards
D a negative charge traveling left to right in a field directed downwards

Homework Equations

The Attempt at a Solution


Ans is D. but i can't understand. it's an electric field. flemming rules don't apply. why is D correct. and the other wrong. shouldn't a -ve charge just move vertically up??
 

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I think you should assume that the particle enters the
region in which the field exists with a certain speed.
 
andrevdh said:
I think you should assume that the particle enters the
region in which the field exists with a certain speed.
even with this assumption, won't an electron moved up in a field directed downward?
 
The charge enters the field moving downwards at an angle and gradually turns upwards.
The field indicates the direction of the force on positive charge, so negative charge experiences
an upwards force. This means that its direction of motion is turned upwards while it is moving along.
 
andrevdh said:
The charge enters the field moving downwards at an angle and gradually turns upwards.
The field indicates the direction of the force on positive charge, so negative charge experiences
an upwards force. This means that its direction of motion is turned upwards while it is moving along.
thanks. so, we had to assume the charge enters at an angle.
i've been thinking for a long time on the question, but never assumed this
 
Yes the path/curve bends downwards a bit
where it enters the field.
 
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