Q:  Determine the power supplied by current source in given circuit.

Answer:

            Power = 1 A (V₁)

By applying KCL at node 1

                                    (V₁/10) - I_x = 1

            By apply KCL at node 2

                                                I_x+ ((V₂-2)/ 7)+ (V₂/5) =0

            Now, three unknown quantities cannot be calculated through 2 equations, therefore try super node technique,

Super node equation will be

                                     (V₁/10) + (V₂/5) + ((V₂-2)/7)=1

            By simplifying it, we may write

                                    35 V₁+120 V₂ = 450

            Also the constraint or coupling equation will be

                                    V₁ - V₂ = 6

            By concurrently solving the two equation

            35V₁+120V₂=450 ...................(1)

                         V₂ = V₁ - 6

By putting the value of V₂ in 1 we get

       35V₁ + 120(V₁ - 6) = 450

       35V₁ + 120V₁ -720 = 450

                             155 V₁= 1170

                                   V₁= 7.55V

            Hence,       V₁= 7.55 V

                          and   V₂ = 1.55 V

Therefore, power

            P = 1(A) (V₁) = 7.55 W