What does it mean for the holes to have mass? But they are not physically existent.
You realise that there is a phenomenon that is represented by the concept of a hole, and that a hole can have a position and a charge right? Starting from there:
When you apply an constant electric field to a hole, it's v-t graph is a straight line with a non-zero slope. ie. it accelerates. Applying Newton's law: F = qE = ma... where q is the charge of the hole and m is it's mass.
The inertia of the hole is an emergent property from the motion of the electrons ... you have to do some work to accelerate all these electrons to give the appearance that there is a positive charged thingy moving the other way.
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