LCD's - uniform electric field

Masafi

I have attached the question, and the answer. I dont understand the answer given.

Attached Files

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berkeman

I agree that the answer is a bit obtuse, but do you understand how there is a torque on an electric dipole in an E-field? You can draw the F=qE force vectors if that helps...

Masafi

It is an uniform electric field, but the forces are not collinear... Why is this?

berkeman

The forces are parallel when the dipole is sideways to the field, and colinear after the dipole aligns with the field. Can you draw the forces on a dipole, and describe what those forces will do to the dipole?