Question

1. solve for total current in the circuit below.

a. 12a b. 1.2a c. 1.2ma d. 12ma

1. solve for the resistive value of resistor number two.

a. 25k ohms b. 30k ohms c. 35k ohms d. 40k ohms

Explanation:

Question 18

Step1: Calculate current through \(R_3\)

Using Ohm's law \(I = \frac{E}{R}\). Given \(E_T=60V\) and \(R_3 = 10k\Omega=10\times10^{3}\Omega\), then \(I_3=\frac{60}{10\times 10^{3}}=6mA\)

Step2: Calculate total current

In a parallel circuit, \(I_T=I_1 + I_2+I_3\). Given \(I_1 = 4mA\), \(I_2=2mA\) and \(I_3 = 6mA\), then \(I_T=4 + 2+6=12mA\)

Step1: Use Ohm's law for resistor \(R_2\)

In a parallel circuit, \(E_T = E_2\) (voltage across parallel - connected components is the same). Ohm's law is \(R=\frac{E}{I}\). Given \(E_T = 60V\) and \(I_2=2mA = 2\times10^{-3}A\)

Step2: Calculate \(R_2\)

\(R_2=\frac{60}{2\times 10^{-3}}=30\times10^{3}\Omega = 30k\Omega\)

Answer:

d. \(12mA\)

Question 19