No credit will be given for answers without appropriate supporting work. Minimum

Question

No credit will be given for answers without appropriate supporting work. Minimum good presentation requires the following: (1) Symbolic expression for any formula, (2) Manipulation of symbolic expressions, not numeric expressions, (3) Substitution of numbers with units, (4) Reporting final answers with correct units and vector expressions, (5) Enough English description to allow the reader to have some idea what you are doing without looking at the math.

Open-Response Homework Problem 8.4 Consider the system of resistors to the right. The battery voltage is ?V0 = 12V. Even numbered resistors, R2, R4, and R6 are 2? and odd number resistors, R1, R3, and R5 are 4?.

(a)What is the equivalent resistance of circuit?

(b)What is the current through R5?

(c)What is the current through R3?

(d)What is ?V4, the potential difference across R4?

(e)How much power does R4 consume?

Explanation / Answer

a)   R2, R3 are parallel

R23 = 2x4/2+4 = 8/6 = 1.33

Now remaining all are in series

R1+ R23+ R3+R4+R5+R6 =4+1.33+4+2+4+2 = 17.33

Req = 17.33

b)  

P =E2/Req

P = 144/17.33 =8.31 watts

I= E/Req = 12/17.33 = 0.69A

Now current R5 is

I(R5) = P/ R5 = 8.31/4 = 2.078A

c)   I(R3) = 12 x1.33 /17.33 = 0.92A

d)   V4 = I x R4 = 0.69 x 2 = 1.38V

e)   P(R3) = I2 R3 = 0.692 ( 4) = 1.904watts

Related Questions

Navigate

• Browse (All)
• Browse N
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.