Determining Dipole Rotation: Clockwise vs Counterclockwise

AI Thread Summary
The discussion centers on determining the rotation direction of an electric dipole in an electric field, questioning whether it rotates clockwise or counterclockwise. The energy of the dipole is expressed as U = -p.E, indicating stable and unstable equilibrium points at angles of 0 and π, respectively. The angle is defined between the dipole moment and the electric field, leading to confusion about how this angle is measured during rotation. Participants suggest visualizing force vectors on the dipole's charges to better understand the net torque direction. Ultimately, the consensus leans towards the dipole rotating counterclockwise, although clarification on angle measurement remains essential.
nishantve1
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This is not a homework question I encountered this while revisiting the Electric Dipoles .
First of all if someone explains me why the dipole
zDSMv.png

So in the image above which way should the dipole rotate ? Anti Clock Wise or Clock Wise .
What My intuition says is the Energy of a dipole is
U = -p.E
Which is -pEcosθ
So the Energy Graph would be
hkmX9.png

So there's a Stable Equilibrium at 0 and unstable equilibrium at ∏

So what I know is that angle is angle made between the E field and the Dipole moment .
What I am not getting is which way is the angle measured ? So if I rotate the dipole moment all the way to bottom will the angle still be same ? Like in the figure ?
zDEPl.png


Also still which way the dipole rotate it seems easier for it rotate counter clockwise . But Will it ?
 
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To get the angle, you need to know which way the dipole vector p is directed, and compare that direction with the direction of E.

Alternatively, you could draw force vectors on the (+) and (-) charges, and from that figure out in what direction the net torque is acting.
 
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