Homework on quiz i took alredy

[c-murda]

Homework Statement

Charges +Q and –Q are arranged at the corners of a square as shown. When the electric field and the electric potential V are determined at P, the center of the square, we find that

Homework Equations

(+Q)---------------(-Q)


-----------P----------- There is line crossging through P from top left +Q and to bottom right +Q and same for -Q's


(-Q)---------------(+Q)

The Attempt at a Solution

1. E = 0 and V > 0
2. E ≠ 0 and V < 0
3. E= 0 and V= 0
4. E ≠ 0 and V > 0
5. None of these is correct. 0%

 

[kuruman]

If you took this quiz already as you seem to imply in the title, what answer did you give and what was your reasoning?

 

[rickysio]

Question seems to be chopped off?

 

[c-murda]

If you took this quiz already as you seem to imply in the title, what answer did you give and what was your reasoning?

i choose none of these are correct because none of them seemed correct to me. notic the 0% next to the last option(none of these are correct)

Question seems to be chopped off?

the question is there in full. it was a multiple choise question.

 

[xcvxcvvc]

i choose none of these are correct because none of them seemed correct to me. notic the 0% next to the last option(none of these are correct)



the question is there in full. it was a multiple choise question.

That isn't a reason. That is circular reasoning.

 

[Borek]

Let's start with the electric filed - how do you think, what is electric field in P?

 

[c-murda]

are the two fields canceled by the push and pull of the oppositely charged particles...leading to 0

 

[Borek]

Right. It is even easier if you think in terms of the definition - force acting on the unit charge. If you place any charge in point P is it pulled in two opposite directions - and these pulls cancel out, and it is pushed in two opposite directions - once agin, forces cancels out.

What about potential?

 

[c-murda]

Right. It is even easier if you think in terms of the definition - force acting on the unit charge. If you place any charge in point P is it pulled in two opposite directions - and these pulls cancel out, and it is pushed in two opposite directions - once agin, forces cancels out.

What about potential?

Since potential is a scalar, you can just add up the value and account for sign. I can see that for every positive charge at a fixed distance there is a corresponding negative charge. This is why when I add it up, the net potential is zero.

So E=0 and V=0?

 

[xcvxcvvc]

Since potential is a scalar, you can just add up the value and account for sign. I can see that for every positive charge at a fixed distance there is a corresponding negative charge. This is why when I add it up, the net potential is zero.

So E=0 and V=0?

yes.