A man crosses a river in a boat if he crosses the river in minimum time he take 10min with a drift 120metre if he crosses the river taking shortest path he takes 12.5min find the width of the river Incoming search terms:crossing a river in shortest distance and timecrossing the river in minimum timephysics [...]

## Derive an expression for current in terms of drift velocity. (Derive I = nAev)

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Consider a conductor of length l and area of cross section A. Let the number of free electrons per unit volume be n. When a pd V is applied, let the