The speed of the ordered movement of electrons in a wire changes with time according to the equation 4 * 10 ^ -5 * t, m / s. The specific resistance of the metal is 2.5 * 10 ^ -6 Ohm * cm, the concentration of free electrons is 2.5 * 10 ^ 23 cm ^ -3, the cross-sectional area of the wire is 5 mm ^ 2. Find: the charge that has passed through the cross-section of the wire in a time interval from 2 s to 4 s; the strength of the electric field E in the wire at a time equal to 2 s; time dependence of the specific thermal power of the current.

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