Question

Consider Figure 13.59. Assume that the dipole is fixed in position. (a) What is the direction of the electric field at location A due to the dipole? (b) At location B? (c) If an electron were placed at location A, in which direction would it begin to move? (d) If a proton were placed at location B, in which direction would it begin to move? (e) Now suppose that an electron is placed at location A and held there, while the dipole is free to move. When the dipole is released, in what direction will it begin to move?

Short answer

(a) The direction of the electric field at location A due to the dipole is at the opposite direction of the dipole.

(b) Thedirection of the electric field at location A due to the dipole is at the same direction of the dipole.

(c) Theelectron will move towards the direction of the dipole.

(d) Theproton will move towards the direction of the dipole.

(e) Thedipole will move towards the direction of the electron which is at the location A.

Step-by-step solution

Significance of the direction of an electric field due to a dipole

The electric field is mainly described as a region that is helpful for an electrically charged particle to exert force on another particle. The direction of the electric field at a point due to a particular dipole will be in the direction of the dipole if the point is situated radially to the dipole and the direction of the electric field will be opposite if the point is situated perpendicular to the dipole.

(a) Determination of the direction of the electric field at location A

From the above figure, it has been observed that location A is situated perpendicular to the dipole. Hence, the direction of the electric field will be opposite of the point.

Thus, the direction of the electric field at location A due to the dipole is at the opposite direction of the dipole.

(b) Determination of the direction of the electric field at location B

From the above figure, it has been observed that location B is situated radially to the dipole. Hence, the direction of the electric field will be same of the dipole of the point.

Thus, the direction of the electric field at location B due to the dipole is at the same direction of the dipole.

 Step 4: (c) Determination of the movement of the electron

If an electron is being placed at location A, then the electron will move towards the positive charge of the dipole. The reason the electron will move towards the positive charge is that due to the law of attraction, the negatively charged electron will get attracted towards the positive charge.

Thus, the electron will move towards the direction of the dipole

(d) Determination of the movement of the proton

If a proton is being placed at location B, then the proton will move towards the negative charge of the dipole. The reason the proton will move towards the positive charge is that due to the law of attraction, the positively charged proton will get attracted towards the negative charge.

Thus, the proton will move towards the direction of the dipole.

(e) Determination of the movement of the dipole

If an electron is being placed at location A and held there, then the positive charge of the dipole will move towards the electron that is negatively charged. The reason the dipole will move towards the electron is that due to the law of attraction, the negatively charged electron will get attracted towards the positive charge, the point of the dipole.

Thus, the dipole will move towards the direction of the electron which is at location A.