The specific thermal power of the current in the conductor varies with time: w = 1.6 * 10 ^ 2 * t ^ 2 W / m ^ 3. The concentration of free electrons in the conductor is 2.5 * 10 ^ 23 cm ^ -3; their mobility is 10 ^ -3 m ^ 2 / V * s. Find: current density and electric field strength in the conductor at time equal to 5 s; the amount of heat released in a volume of 30 cm ^ 3 of the conductor in the first 10 s.

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