Dipole in an Uniform Electric Field:

In summary, the torque on a dipole in an uniform electric field is calculated as FLsin(x) = qELsin(x) = pEsin(x), with the direction of the torque vector being into the paper. This torque tends to align the dipole moment vector with the direction of the electric field. It can also be expressed as T = p x E. The magnitude of the torque is found by taking the cross product of the force and the lever arm, which in this case is the distance between the charges in the dipole. The dipole moment is defined as L*q, so qELsin(x) = pEsin(x) by definition. It is important to understand the concepts of torque and vectors to fully grasp
  • #1
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Dipole in an Uniform Electric Field:
torque is calculated about the position of either charge has the magnitude FLsin(x) = qELsin(x) = pEsin(x). The direction of the torque vector is into the paper such that it tends to rotate the dipole moment vector p so it aligns with the direction of E. The torque can be expressed most concisely as the cross product: T = p x E

I don't know why the magnitude is F * L sin(x) or why qE turns into pE. And I don't understand what the concept iit s trying to tell me. It would also be helpful if someone could explain the hand thing for torque. I understand most of the stuff about torque but not the hand thing.

x = theta
L = distance between charges in dipole
p = vector of the dipole movement that points from negtive charge to positive.
p =q*L
 
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  • #2
The dipole moment is defined as being L*q, so qELsin(x) = pEsin(x) by definition. As for F*L*sin(x), that's simply the scalar form of the vector cross product of F x L. Torque is defined as the cross product between the force vector and the vector denoting the lever arm. To find the torque on a dipole, they fix one of the charges as the center of rotation (or choose the midpoint, the result is the same since the magnitude of the force is the same) and assume that the length between the charges (or the dipole moment) to be the lever arm. The force is the Lorentz force resulting from the electric field.

I think you should brush up on torque and vectors because these are very basic concepts.
 
  • #3


Hello there,

I can explain the concept of torque and its relation to a dipole in an uniform electric field. Torque is a force that causes rotation or twisting, and it is calculated by multiplying the force applied by the distance from the pivot point. In this case, the pivot point is the position of either charge in the dipole.

When a dipole is placed in an uniform electric field, it experiences a torque due to the interaction between the charges and the electric field. This torque is calculated as FLsin(x), where F is the force applied, L is the distance between the charges in the dipole, and x is the angle between the force and the dipole moment vector p. The dipole moment vector p is a vector that represents the strength and direction of the dipole, and it points from the negative charge to the positive charge.

In the equation, qE is used to represent the force applied on the dipole due to the electric field. This is because the electric field exerts a force on the charges in the dipole, causing them to experience an opposite force and creating a torque. The magnitude of this force is equal to qE, where q is the charge of the dipole and E is the strength of the electric field.

The direction of the torque vector is into the paper, which means it is perpendicular to the plane of the dipole and the electric field. This torque tends to rotate the dipole moment vector p so that it aligns with the direction of the electric field. This can be seen by imagining a hand turning a screwdriver. The hand represents the torque vector and the screwdriver represents the dipole moment vector. The hand turning the screwdriver causes it to rotate and align with the direction of the force.

In summary, the equation for torque in a dipole in an uniform electric field is T = p x E, where p is the dipole moment vector and E is the strength of the electric field. This equation represents the interaction between the charges in the dipole and the electric field, and how it causes the dipole to rotate and align with the electric field. I hope this explanation helps clarify the concept for you.
 

What is a dipole in an uniform electric field?

A dipole in an uniform electric field is a system consisting of two equal and opposite charges (positive and negative) separated by a small distance, placed in an electric field that has the same strength and direction at all points.

What is the direction of the dipole in an uniform electric field?

The direction of the dipole in an uniform electric field is from the positive to the negative charge. This direction is also known as the dipole moment and is represented by an arrow pointing towards the negative charge.

What is the magnitude of the electric field at the center of a dipole?

The magnitude of the electric field at the center of a dipole is zero. This is because the electric fields produced by the two charges cancel each other out at the center point.

What happens to the dipole in an uniform electric field when the field strength changes?

When the field strength changes, the orientation of the dipole may also change. If the field strength increases, the dipole may align itself in the direction of the field, while if the field strength decreases, the dipole may align itself in the opposite direction.

How is the torque on a dipole in an uniform electric field calculated?

The torque on a dipole in an uniform electric field is calculated by multiplying the magnitude of the electric field by the dipole moment and then taking the sine of the angle between the electric field and the dipole moment. This can be represented by the equation: Torque = E * p * sin(theta).

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