# Homework Help: Wiring diagram/sheep a series

1. Jan 26, 2010

### aloshi

Hello!!
I read electricity now, and can not to understand certain things.

if we link so that we sheep a series, type [PLAIN]http://img38.imageshack.us/img38/8613/scheman.jpg [Broken] [Broken]

1) what is it that do that electrons used to draw/thread from the negative pole to positive pole? if you say that they are voltage over, but the voltage is: http://www.pluggakuten.se/wiki/images/b/be/111.JPG [Broken]
that work we must give the electron to have move from p_2 to p_1.

2) does, there is an electrical field in the wiring diagram? ([PLAIN]http://img38.imageshack.us/img38/8613/scheman.jpg [Broken] [Broken])

3) Why accelerates electrons in a circuit (sow as the picture)? if we say that there be a homogeneous electrical field/fields,
in a homogeneous electrical field are the force, F, same.

Last edited by a moderator: May 4, 2017
2. Jan 26, 2010

### Gokul43201

Staff Emeritus
It looks like you are using a translation software to write this post, so it is a little difficult to understand.

1) Which direction does the electric field point? What is the equation for the force on a charge (Q), placed in an electric field (E)? What do you know about the charge of an electron? Therefore, in what direction is the force acting on an electron when it is placed in the electric field shown in the figure?

2) Yes, there is an electric field present along the wires as well. The field lines follow the same basic rules: they start from the positively charged pole and end in the negatively charged pole.

3) I can not exactly understand the question, but here's something to think about. There is a uniform force on the electrons from the electric field, but there is also another important force on them. What is it?

3. Jan 27, 2010

### aloshi

a new question:
why the electron in a solid accelerate? you said that there is electric field in a solid, right? Like this [PLAIN]http://img38.imageshack.us/img38/8613/scheman.jpg [Broken] [Broken]
The electrical field force is constant, so how can it accelerate

a new question :
why the electron in a solid accelerate? you said that there is electric field in a solid, right? Like this [PLAIN]http://img38.imageshack.us/img38/8613/scheman.jpg [Broken] [Broken]
The electrical field force is constant, so how can it accelerate?
1)
Which direction does the electric field point?
answer: it goes always from positive the pole to the negative pole

What is the equation for the force on a charge (Q), placed in an electric field (E)? What do you know about the charge of an electron?
answer: when we place a charge in an electrical field, then wants the charge follow the electrical field direction. but the electron has/have a negative charge and they dont follow the electrical field direction. if we will the electron to follow the electric field direction, we need to do a job/work. this job/worke are W=Q*E*d, Q=charge (electron) ,E=electrical field, d=distance, see Figure http://www.pluggakuten.se/wiki/images/b/be/111.JPG [Broken]

Therefore, in what direction is the force acting on an electron when it is placed in the electric field shown in the figure?
the force acting direction, against / to positive pole. On the picture, from p_1 to p_2.

2)
but the electron will move from the negative pole to positive pole

3)I do not know what force you are talking about. you mean gravitational force ((F=mg), m=mass and g=9,82m/s^2)?

Last edited by a moderator: May 4, 2017
4. Jan 27, 2010

### aloshi

1)
Which direction does the electric field point?
answer: it goes always from positive the pole to the negative pole

What is the equation for the force on a charge (Q), placed in an electric field (E)? What do you know about the charge of an electron?
answer: when we place a charge in an electrical field, then wants the charge follow the electrical field direction. but the electron has/have a negative charge and they dont follow the electrical field direction. if we will the electron to follow the electric field direction, we need to do a job/work. this job/worke are W=Q*E*d, Q=charge (electron) ,E=electrical field, d=distance, see Figure http://www.pluggakuten.se/wiki/images/b/be/111.JPG [Broken]

Therefore, in what direction is the force acting on an electron when it is placed in the electric field shown in the figure?
the force acting direction, against / to positive pole. On the picture, from p_1 to p_2.

2)
but the electron will move from the negative pole to positive pole

3)I do not know what force you are talking about. you mean gravitational force ((F=mg), m=mass and g=9,82m/s^2)?

a new question :
4)why the electron in a solid accelerate? you said that there is electric field in a solid, right? Like this http://img38.imageshack.us/img38/8613/scheman.jpg [Broken]
The electrical field force is constant, so how can it accelerate

Last edited by a moderator: May 4, 2017
5. Jan 27, 2010

### Gokul43201

Staff Emeritus
Again, it is very difficult to understand your post, but I'll try.

correct

Yes. In short, a positive charge feels a force that is in the same direction as the field, and a negative charge (like the electron) feels a force in the opposite direction to the field.

Correct. The electron will move from p1 (negative pole) to p2 (positive pole)

This is exactly what you determined above.

No, gravitational effects can be neglected. In addition to the force on the electron from the electric field, there is a second force that opposes the motion.

In general, a constant net force will produce a constant acceleration. That is Newton's Second Law. But in this case, the force from the electric field is opposed by a drag force caused by collisions with atoms in the solid, and that drag force is what gives rise to the property known as resistance.

Last edited by a moderator: May 4, 2017
6. Jan 27, 2010

### aloshi

Which direction the electrons take in a solid?

I think they go from the negative pole to positive pole because the electrons will have a potential energy and when the electron be/(find oneself) in the negative pole they will have a potential energy. and when we have a solid, the potential energy to become kinetic energy.
have i think right?

7. Jan 27, 2010

### Gokul43201

Staff Emeritus
The electrons always go from the negative pole to the positive pole, because the electric field is in the opposite direction.

Another way of thinking about this is that similar charges repel and opposite charges attract. The electron is negatively charged, so it is repelled by the negative pole and attracted by the positive pole.

The importance of the wires, is that they provide a pathway for the electrons to travel from one pole to the other.

8. Jan 27, 2010

### aloshi

http://www.pluggakuten.se/wiki/images/d/da/Krets.jpg [Broken]
why is not the same voltage for the 640 ohm resistor and 320ohm.
Current is 22.5 mA according to the image.
what is the voltage? Voltage = work to do last a ccertain distance charge d.

I know it has to resistancein the solid, but I do not know what it is. can you explain to me, thanks

Last edited by a moderator: May 4, 2017