Explore BrainMass

Explore BrainMass

    Electrostatics - Electric dipole

    Not what you're looking for? Search our solutions OR ask your own Custom question.

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    For two equal in magnitude but opposite charges +Q and -Q we can define a vector of dipole moment p, with the magnitude absolute value (p)=dxQ, where d is the distance between the charges. The direction of p is the direction from negative to positve charge (see figure)

    1.)What force acts on the dipole in a uniform electric field E.

    2.)What torque is acting on the dipole.

    © BrainMass Inc. brainmass.com December 24, 2021, 7:46 pm ad1c9bdddf
    https://brainmass.com/physics/torques/electrostatics-electric-dipole-218014

    Attachments

    SOLUTION This solution is FREE courtesy of BrainMass!

    Please refer to the attachment.

    +Q F

    p d dsinθ E
    θ
    - F -Q

    A +ve charge experiences a force in the direction of the electric field vector E and -ve charge opposite to it. Hence, the forces acting on the charges of the dipole are as shown in the fig..

    Magnitude of force on each charge = F = QE (Because by definition electric field intensity at a point is the force experienced by a unit positive charge placed at that point. Hence, force experienced by a charge Q placed at that point is QE)

    1) Net force acting on the dipole = 0 (as forces F and -F cancel out).

    2) Torque acting on the dipole = τ = Force x Perpendicular distance between the line of action of the forces = QE x dsinθ = (Qd)Esinθ = pEsinθ

    τ = pEsinθ

    In vector form : τ = p X E (cross product of vectors p and E)

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    © BrainMass Inc. brainmass.com December 24, 2021, 7:46 pm ad1c9bdddf>
    https://brainmass.com/physics/torques/electrostatics-electric-dipole-218014

    Attachments

    ADVERTISEMENT