(Solved): In the circuit shown in the figure below, the two thick wires and the thin wire are made of Nichro ...

In the circuit shown in the figure below, the two thick wires and the thin wire are made of Nichrome. The emf of the battery is \( 1.5 \mathrm{~V} \). In Nichrome there are \( n=9 \times 10^{28} \) mobile electrons per \( \mathrm{m}^{3} \), and the mobility of mobile electrons is \( u=7 \times 10^{-5}(\mathrm{~m} / \mathrm{s}) /(\mathrm{N} / \mathrm{C}) \). Each thick wire has length \( L_{1}=30 \mathrm{~cm}=0.30 \mathrm{~m} \) and cross-sectional area \( A_{1}=9 \times \) \( 10^{-8} \mathrm{~m}^{2} \). The thin wire has length \( L_{2}=3 \mathrm{~cm}=0.03 \mathrm{~m} \) and cross-sectional area \( A_{2}=1.7 \times 10^{-8} \mathrm{~m}^{2} \). (The total length of the three wires is \( 63 \mathrm{~cm} \).) In the steady state, calculate the number of electrons entering the thin wire every second. Do not make any approximations, and do not use Ohm's law or series-resistance equations. electrons/s