A neutral conductor (or dielectric) experiences a torque, but no net force, when placed in a uniform electric field. It does experience a net force in a non-uniform field.
What it shows:
When an electrically neutral object is suspended in a uniform electric field, it becomes polarized. The electric force on the separated charges produces a torque about the suspension point and the object rotates. There is no translational motion—the object simply aligns itself with the electric field.
When an electrically neutral object is...
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