Find the direction of a electric field

AI Thread Summary
The direction of an electric field is determined by the movement of a positive test charge, always pointing away from positive charges and toward negative charges. In the case of two plates, if one plate is at a higher negative potential, the electric field will point from the plate with the higher potential (A at -200V) to the lower potential (B at 0V). Therefore, the electric field direction is from plate A to plate B. Understanding this concept is crucial for analyzing electric fields in various configurations. The discussion emphasizes the importance of recognizing the relationship between electric potential and field direction.
Zanatos
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Hey, My problem is that I am getting confused (although getting the answer right :confused:) on how to find the direction of a electric field, for example (right or left). I know it has something to do with a test charge but can anyone quickly explain it to me.

~THX
 
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Imagine the electric field as a banch of arrows (vector), the field ALWAYS points OUT from the POSITIVE charge and points INTO the NEGATIVE charge...

The force acts on the test charge follows the direction of the E-field if the test charge is POSITIVE, and oppose to the field if the test charge is NEGATIVE...
 
Its easy mate, Electric field lines are directed from the higher potential to the lower potential.

So assume we have two plates, A and B. Assume B is earthed ( 0V) and plate A is at a potential of -200V.

So what would be the direction of the elctric field. From A to B or B to A.
 

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