Consider the circuit in Fig. P6.51 with the base voltage VB obtained using a voltage divider across the 5-V supply. Assuming the transistor β to be very large (i. e., ignoring the base current), design the voltage divider to obtain VB = 1.5 V. Design for a 0.1-mA current in the voltage divider. Now, if the BJT β = 100, analyze the circuit to determine the collector current and the collector voltage.

An air-conditioning system consists of a heating section and an evaporative cooler. air enters the heating section at 10°c and 70 percent relative humidity at a rate of 30m^3/min, and it leaves the evaporative cooler at 20°c and 60 percent relatively humidity. if the air conditioning system operates at a total pressure of 98 kpa, determine (a) the temperature and relative humidity of the air when it leaves the heating section, (b) the rate of heat transfer in the heating section, and (c) the rate of water added to air in the evaporative cooler