Work done and potential

In my class X physics book it is written that the expression W=QV "is analogous to the amount of work needed in lifting a weight mg from the earth surface to a vertical height h which is given as W=mg x h = mgh. Obviously on comparison of the expressions W=QV and W=mgh, we find that the charge Q is analogous tot he weight mg and the potential V is analogous to height h."
But I don't think it's obvious. How can charge correspond to mg, i.e. a force? Charge can correspond to mass, both of which are internal properties of matter. Even, I do not understand how h can be analogous to V. h is distance while V is potential, i.e., energy per unit charge/mass (as the case may be). Please explain.

Thanx...

2 Answers

206
Sayantan Hazra ·

The charge Q is not analogous to the force mg.....it is analogous only to the mass m.......

The potential V can be expressed as V = E.d, where E is the electric field and d is the distance between which potential is taken (you will study this later)

The product of the Electric Field E and charge Q is analogous to the force mg, i.e, QE is analogous to mg, and d is analogous to h.

337
Sayan Sinha ·

Thanx...

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