Q. Determine voltage at all nodes and current by all branches. Suppose β=100.

Solution:

                                Applying Thevenin's theorem the circuit takes the shape as given in the figure.

                                                                                Through writing

                                                                V_BB=15(R_B2)/(R_B1+R_B2)

                                                                       =15(50)/150=5V

                                                                R_BB=R_B1||R_B2

                                                                        =100||50=33.3kW

                                                Writing the KVL equation for loop L

                                                                     V_BB=I_BR_BB+V_BE+I_ER_E

                                                  Place          IB=IE/(β+1)

The base current can be

                                                                    I_B=1.29/101=0.0128mA

Thus the base voltage is

                                                                      V_B=V_BE+I_ER_E

                                                                         =0.7+1.29(3)=4.57V

Presuming active mode the collector current should be

                                                               I_C=αI_E=0.99(1.29)=1.28mA

                                                And               V_C=15-I_CR_C=15-1.28(5)=8.6V