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# Irratating A2 Physics Question. Watch

1. It is multiple choice, I know what the Answer is so please could you provide an explanation of the answer as I don't understand why thanks

Which one of the following statments about electric field Strength and electric potential is incorrect?

1. Electric Potential is a Scalar Quantity
2. Electric Field Strength is a Vector Quantity
3. Electric Potential is zero whenever electric field strength is zero
4. The Potential Gradient is Proportinal to the electric field strength

Thanks, I wont say the answer because I want to be sure that people that give an answer truly understand it (and so hopefully give the right one)

Thanks for any help!
2. its 3. simple
3. I haven't done fields yet, but I think the answer is 2 - is that right?
4. (Original post by Shortduct)
I haven't done fields yet, but I think the answer is 2 - is that right?
No.
5. 3 ?
6. Could you please Explain why, The answer isn't important. I know it can be worked out by process of elimination (or just getting the correct answer) But I'd like to understand why
7. Vaguely I think it is 3 because of the charged sphere thing...
8. (Original post by QuantumOverlord)
Could you please Explain why, The answer isn't important. I know it can be worked out by process of elimination (or just getting the correct answer) But I'd like to understand why
The simple fact that Electric field is a vector quantity and electric potential is a scalar should answer your q.
9. (Original post by rbnphlp)
The simple fact that Electric field is a vector quantity and electric potential is a scalar should answer your q.
Unfortuntely it doesnt :/
10. (Original post by QuantumOverlord)
It is multiple choice, I know what the Answer is so please could you provide an explanation of the answer as I don't understand why thanks

Which one of the following statments about electric field Strength and electric potential is incorrect?

1. Electric Potential is a Scalar Quantity
2. Electric Field Strength is a Vector Quantity
3. Electric Potential is zero whenever electric field strength is zero
4. The Potential Gradient is Proportinal to the electric field strength

Thanks, I wont say the answer because I want to be sure that people that give an answer truly understand it (and so hopefully give the right one)

Thanks for any help!
Potential is a scalar, this is correct. EFS is a vector (think field lines), this is correct. Potential gradient is deltaV/deltaR; however EFS = -deltaV/deltaR so this is correct. The second last one is incorrect and hence the right answer.
11. (Original post by QuantumOverlord)
Unfortuntely it doesnt :/
say if you had a electric field strenght of 0, but say 2 opposite charges of equal magnitude seperated by a distance r , the potential does not equal 0..(try some no's if you wish)
12. (Original post by QuantumOverlord)
It is multiple choice, I know what the Answer is so please could you provide an explanation of the answer as I don't understand why thanks

Which one of the following statments about electric field Strength and electric potential is incorrect?

1. Electric Potential is a Scalar Quantity
2. Electric Field Strength is a Vector Quantity
3. Electric Potential is zero whenever electric field strength is zero
4. The Potential Gradient is Proportinal to the electric field strength

Thanks, I wont say the answer because I want to be sure that people that give an answer truly understand it (and so hopefully give the right one)

Thanks for any help!
13. (Original post by Farhan.Hanif93)
3 is incorrect according to the markscheme from AQA, i.e. 3 is the correct answer.

E=Q/(4 x pi x epsilon x r^2)

There is no account of V in that equation.
14. (Original post by l4ith)
3 is incorrect according to the markscheme from AQA, i.e. 3 is the correct answer.

E=Q/(4 x pi x epsilon x r^2)

There is no account of V in that equation.
I said that it was a counterexample to (3) i.e. I was saying that statement (3) is incorrect.
Statement (3) is the right answer to the question.
15. (Original post by Farhan.Hanif93)
I said that it was a counterexample to (3) i.e. I was saying that statement (3) is incorrect.
Statement (3) is the right answer to the question.
Oh right yeah I agree with you then
16. (Original post by Farhan.Hanif93)
I said that it was a counterexample to (3) i.e. I was saying that statement (3) is incorrect.
Statement (3) is the right answer to the question.
I guess he was referring to the previous deleted post
17. (Original post by rbnphlp)
I guess he was referring to the previous deleted post
Damn, you saw it hahaha!
I think there was actually some confusion with the post he quoted of mine as there was a lot of ambiguity in it.
18. Ok, I am going to give a scientifically induced explanation and a simple explanation with an example.
Scientifically:

Electric Field is related to potential as:

E=- \frac{dV}{dR}

E can only be zero if V is constant .

So what can be the possible condition as per above such that V is zero when E is zero? Is it possible? ..What are the possible conditions in which V can be zero?

Or simply:
All theyre trying to say is that Electric field strength is a vector quantity and electric potential is a scalar quantity. Suppose you have an electric field strength of 0Vm^{-1} acting on a test charge by 2 charge particles of 1C and -1C. The electric potential in this case wouldnt be 0, it would be 2V.
19. (Original post by Farhan.Hanif93)
Damn, you saw it hahaha!
I think there was actually some confusion with the post he quoted of mine as there was a lot of ambiguity in it.
I just remembered the post so I didn't really read the other one close enough, sorry!
20. (Original post by l4ith)
I just remembered the post so I didn't really read the other one close enough, sorry!
No problem, an awkward-to-word answer normally results in confusion.

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