C2 Circuits (Chapter 18)  Homework

50 points


18.1 Resistance in parallel, series and series parallel circuits.

1-8, 11, 13, 17-22, 25, 26, 29, 33, 34, 36


8:  draw it!  Find R parallel for the entire circuit

19:  find Rparallel for 8W and for the 4W.  Then, find Rseries for Rp8 and Rp4.  Remember, since the resistor are in parallel with each other, you must divide the ultimate current through each resistor by two since the resistors (in parallel) have the same resistance.

25:  Find Rseries.  Then, determine Iseries.  Then, determine VR3 based on Iseries and 10 volts.  Then, determine VR1+R2 since VR1+R2 + VR3 must equal 10 volts.  Finally, determine IR1 based on VR1+R2 and R1

29:  Find Ptotal by summing the watts.  Recall that I = P/V and V is fixed at 120V.

33:  First, know that P = V2/R.  Find each individual resistance for e each bulb.  Then, find equivalent resistance of the entire circuit.  Realize that 15W and 40 W are in series with each other.  60W and 100 W are in parallel with each other but are in series with 15/40W.  Realize I will be the same for each resistor since that are all in a series circuit so you must find Iseries.

36:  Break it down and decide which is in series and which is in parallel with each other.


18.2 Kirchhoff’s Rules

39, 40, 41

41:  you are going from low to high potential.


18.3 RC Circuits




2:  a

4:  no;  only if all resistances are equal

6: 1W; it gets the most current for the same voltage

8:  10W

18:  a)  11A   b)  2W = 6A,     4W = 3A,      6W = 2A     c) 2W = 72W,     4W = 36W,      6W = 24W    d) Ptotal = 132W      

20:  0.80W

22:  7.5W

26:  a)  0.42A; 0.83A; 1.25A      b)  290W;  144W;  96W

36:  8.1W

40:  c

52:  a

54:  d

56:  a) 1.5 sec   b)  99.995%

58:  0.693 t

60:  a) 24V   b) 0   c) 4.0A