Question

True or false Electrical Potential Question based on graphs :

Answer 1

1) An electric dipole with its positive charge at y = 0.01 mm and its negative charge at y = -0.01 mm placed at x = 2 m in Diag. A and released will initially rotate clockwise.
2) A negative charge placed at x = 4 m in Diag. A and released will accelerate left.
3) The electric potential at x = 4 m in Diag. A is larger than the electric potential at x = 5 m in Diag. B.
4) The work done by you to bring an HCL molecule from infinity to the point x = 2 m in Diag. A is positive.
5) The magnitude of the electric field at x = 2 m in Diag. A is larger than the magnitude of the electric field at x = 2 m in Diag. B.
6) The electric field at x = 2 m in Diag. A points to the left.

Answer 2

Hi!

I don't understand (1), unfortunately. But I have some concepts that might help you with it and the rest!

Do you know what an "analogy" is, in its English meaning? It's where you have similarities between things that are really different. An "analog" is the description of the similarities amongst these different things.

Can this help? Yes. Because electrical potential energy has an analog. And electrical potential energy is important to electrical potential (voltage).

Electrical potential \(energy\) is like gravitational potential \(energy\). They work similar because they are potential energies from a force field whose strength is inversely proportional to the square of the separating distance. So, there are similarities, though electric force works differently that gravitational force.

If you place a mass in the air (a gravitational field), it has some potential energy. It will go to the place with less potential energy.
If you place a charge in an electric field, it will go to the place where it will have a lesser potential energy. That will depend on it's charge, though.

Think of these two charges - one negative and one positive - where they both go to a lower potential energy:
A positive charge in a positive field has potential energy but will move to where the field is LESS positive.
A negative charge in a positive field has potential energy but will move to where the field is MORE positive.

Now we look at electrical potential. We don't care about the energy, even though it's easy to find from electrical potential. Electrical potential is the electrical potential energy \(per\) \(charge\).
\(V=\rm\dfrac{potential\ energy}{charge}\)
Special Note: the sign of Voltage can be negative even with \(positive\) potential energy.

Back to those two charges, now.
A positive charge in a positive field has potential energy. So it has positive potential energy per charge, which is positive electrical potential. It moves to its lower potential energy, to a less positive electric field still. This is also a movement to a lesser electrical potential.
A negative charge in a positive field has potential energy. So it has positive potential energy per charge, which is negative electrical potential. It moves to its lower potential energy, which is to a greater electrical potential!

This picture sums it up well. When we talk about the potential energy, it's of the charge on the right. When we talk about the electrical potential, it's at the LOCATION of the charge.

Notice that the positive field source is the high electrical potential.
If you do the same for a negative field, you'll see the more negative field area is the lower potential.

Answer 3

So you are given the electrical potential and the sign of the charge for these.

I don't know the charge of \(\rm{HCl}\)....

Answer 4

For (4), I researched that \(\rm{HCl}\) charge briefly and it lines up with my memory. It's neutral. So how much work is done?

Answer 5

Good luck :)