Two electrical Problems I'm stuck on

[Oblio]

hey guys, I'm not sure how to start these off. Can someone give me a hint?


I'm not sure how else to show these (they have circuit pictures). The questions are numbers 18 & 24 here http://www.physics.brocku.ca/Courses/2P31/DH-Asst1.pdf .

thanks in advance :)

 

[user101]

For 18... you know that Vth = Rthv * i_sc. If you remove V, find the equivalent resistance (what do you do with voltage sources? current sources? open or short which one?). Also find the open circuit voltage across your terminals with V2 removed. I'm pretty sure this is what you would do.

 

[unplebeian]

For 24, use nodal analysis. That'll give you an expression of Vnodal as a function of V3.