An 18.0 $\Omega$, 9.00 $\Omega$, and 6.00 $\Omega$ resistor are connected in series with an emf source. The current in the 9.00 $\Omega$ resistor is measured to be 4.00 A. Find the potential difference across the emf source.

What is the voltage difference across the $20-\Omega$ resistor?

Which one gives off more power (as joule heating) when connected across the terminals of a 12-V battery: a $5.0-\Omega$ resistor or a $10-\Omega$ resistor? Explain your reasoning.

Set up systems of equations and solve by Gaussian elimination. The voltage across an electric resistor equals the current (in A) times the resistance (in $\ohm$). If a current of 3.00 A passes through each of the two resistors, the sum of the voltages is 10.5 V. If 2.00 A passes through the first resistor and 4.00 A passes through the second resistor, the sum of the voltages is 13.0 V. Find the resistances.

What happens to the resistance of a common ohmic resistor, if it is heated?

In each blank, insert the most appropriate word

__________________glands discharge their secretions externally through ducts or tubes.

A DC circuit is formed by a 12 V battery and a 5-ohm resistor. Find the current Ir flowing through the resistor. Express your answer to 3 significant figures and include the appropriate unit.

What is the voltage difference across the 9- $\Omega$ resistor?

The resistor, inductor, capacitor, and voltage source described in earlier Exercise are connected to form an $L-R-C$ series circuit.(d) What are the voltage amplitudes across the resistor, inductor, and capacitor?

Choose the most appropriate answer for given of the following question.
Once a patient is discharged, the coder will go through the complete patient record. The most important documentation to look for includes all of the following except
a. the discharge summary.
b. the hospital course.
c. the discharge disposition.
d. all of these documentations are important.

What is the equivalent resistance of the two-resistor parallel combination

A box contains $20$ resistors with $15$ pcs of $100\ \omega$ and $5$ pcs of $50 \ \omega$. What is the probability that the second resistor is $100 \ \omega$, given that the first resistor is $50 \ \omega$?

9 What would be the potential difference $\Delta V_2$ across the thin resistor in Figure 18.61 (between locations B and C) if the battery emf is 1.5 V? Do you have enough information to determine the current I in the circuit? Assume that the electric field in the thick wires is very small (so that the potential differences along the thick wires are negligible).

The voltage drop $V_{a b}$ across each of resistors $A$ and $B$ was measured as a function of the current $l$ in the resistor. The results are shown in the table:

Resistor A
$I(\mathrm{~A})$	0.50	1.00	2.00	4.00
$V_{a b}(\mathrm{~V})V$	2.55	3.11	3.77	4.58
Resistor B
$I(\mathrm{~A})$	0.50	1.00	2.00	4.00
$V_{a h}(\mathrm{~V})$	1.94	3.88	7.76	15.52

(a) For each resistor, graph $V_{a b}$ as a function of $I$ and graph the resistance $R=V_{a b} / l$ as a function of $I$.