Electric Field, Excess Charge Conceptual Question

AI Thread Summary
The discussion revolves around a conceptual question regarding the behavior of a charged balloon in a uniform electric field directed towards the +x direction. Observations indicate that the balloon moves towards the -x direction, suggesting it must have a negative excess charge. The confusion arises from the relationship between electric fields and charge movement, where positive charges move with the field and negative charges move against it. Clarification is provided on the origin of electric field lines, which emanate from positive charges and terminate at negative charges. Ultimately, understanding the interaction between the balloon's charge and the electric field confirms that the balloon has a negative excess charge.
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Homework Statement



1. A balloon is charged with excess charge. This balloon is then put in a space with a
uniform electric field pointing towards +x direction. When there is no wind around,
this balloon is observed moving towards the -x
direction. What is the sign of excess
charge on the balloon?

(A ) Positive.
(B ) Negative.
(C ) Not enough information.
(D) Neutral.

Homework Equations



None

The Attempt at a Solution



I thought the answer was "A" but that is incorrect. I thought so only because of the second to last sentence. I thought of the whole "opposite charges attract." I also don't understand the significance of saying which direction the electric field is in, only that it points from positive to negative.
 
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It is assumed that the electric field is originated from positive charge and radiates away from that. If a positive charge is placed in the electric field, it moves in the direction of the elelctric field due to the repulsion. If the negative charge is placed in the elelctric field what happens?
 
If a negative charge is placed instead it would move in the opposite direction of the electric field. Electric field lines, however, originate from positive charges to negative charges. I think I was mixing those two concepts.
 
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