Physics 12.3.2a - The Electric Field Around a Charge

The electric field around a charged object. From the physics course by Derek Owens. The distance learning course is available at http://www.derekowens.com

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Education

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• Physics
• electric field
• charge
• electric charge
• electric fields
• field lines
• electric field lines
• lines of force
• homeschool
• distance learning
• Derek Owens

[sarwansagar]

why is it necessary to assume the test charge to be positive?



[derekowens]

@sarwansagar It's not necessary to assume the test charge is positive. You could imagine, for example, a negative test charge, and think about how it would behave. However, the direction of the field is *defined* as the direction of the force it would exert on a positive test charge.

[behnamasid]

Does the electric field go out to infinity?

[derekowens]

@behnamasid Yes, but it weakens with distance. If you could go all the way to an infinite distance, then it would weaken all the way to zero.

[punkvijay224]

thanks for uploading...its really helping me a lot...thank from heart>>>>

[Anikaangellove]

we watched your video in our physics class :)

[PaulK0512]

Ugh this makes too much sense.

[Bruinboi16]

a capacitor video would be awesome

[BoroTheYeti]

@derekowens do you have a video about capacitors? thanks

[moezart94]

@derekowens Thanks for answering :) I want to ask you one more question I hope you can help. What are the uses of knowing the directions? Is there any video that explains it?

[derekowens]

@moezart94 Well, you could think of it either way. By convention, we typically think of the test charge as positive. A negative charge would be forced in the opposite direction of a positive charge.

[moezart94]

@derekowens Why isn't the test charge negative? or if it was a negative charge, what would happen?