Repeat Example 7.7 with the resistor R 1 changed to 100. ohms and all other values unchanged.
Question:
Repeat Example 7.7 with the resistor R1 changed to 100. ohms and all other values unchanged.
Example 7.7
Find the current through and voltage across the 40. ohm resistor, R3, in the following circuit.
Need: I3 = ____ A and V3 = ____ V.
Know: Kirchhoff’s current and voltage laws, Equations (7.3) and (7.5).
How: This circuit has four nodes (A, B, C, and D) and two independent loops. Write the current law equations for the two nodes and the voltage law equations for the two loops. Then solve the resulting set of algebraic equations for the currents.
Using Kirchhoff’s current law, for node A the equation is I1 + I2 = I3
Using Kirchhoff’s voltage law around loops 1 and 2, the equations are:
Since I3 is the sum of I1 + I2 we can substitute this into the loop equations and rewrite them as:
Step by Step Answer:
Exploring Engineering An Introduction to Engineering and Design
ISBN: 978-0123747235
2nd edition
Authors: Philip Kosky, George Wise, Robert Balmer, William Keat