Consider the circuit shown in the figure below. (Assume R 1 = 7.00 ?, R 2 = 2.50
ID: 2300443 • Letter: C
Question
Consider the circuit shown in the figure below. (Assume R1 = 7.00 ?, R2 = 2.50 ?, and V = 9.00 V.)
(a) Calculate the equivalent resistance of the R1 and 5.00-? resistors connected in parallel.
?
(b) Using the result of part (a), calculate the combined resistance of the R1, 5.00-?, and 4.00-? resistors.
?
(c) Calculate the equivalent resistance of the combined resistance found in part (b) and the parallel 3.00-? resistor.
?
(d) Combine the equivalent resistance found in part (c) with the R2 resistor.
?
(e) Calculate the total current in the circuit.
A
(f) What is the voltage drop across the R2 resistor?
V
(g) Subtracting the result of part (f) from the battery voltage, find the voltage across the 3.00-? resistor.
V
(h) Calculate the current in the 3.00-? resistor.
A
Explanation / Answer
a.)
Req.. = R1 || 5 = 7 * 5 / (5+7) = 35/12 = 2.916 ? >=========================< ANSWER
b.)
R3 = R1 || 5 + 4 = 2.916 + 4 = 6.916 ? >=========================< ANSWER
c.)
R4 = R3 || 3 = 6.916 * 3 / (6.916+3) = 2.092 ? >==================< ANSWER
d.)
R5 = R4 + R2 = 2.092+2.5 = 4.592 ? >=======================< ANSWER
e.)
Total current = v/R5 = 9 / 4.592 = 1.959 Amps >====================< ANSWER
f.)
VR2 = 2.5 * 1.959 = 4.897 volts >=============================< ANSWER
g.)
V(3ohms) = 9 - VR2 = 9-4.897 = 4.103 volts >====================< ANSWER
h.)
I(3ohms) = 4.103 / 3 = 1.367 Amps >=========================< ANSWER