Question

name:
period:
general
1.
simple series circuit
worksheet 5
draw the schematic
diagram for this circuit
(show direction of current)

1. finish the sentence \conventional current flows from\

a. negative to positive b. positive to negative

1. the proper units of current is a) ohms b) amps c) volts
2. the proper units of resistance is a) ohms b) amps c) volts
3. ohms law is best expressed as a) ( i = vr ) b) ( r/v = i ) c) ( v = ir )
4. true or false: in order to have a successful circuit you must

have a closed loop

1. true or false: the sum of the voltage drops equal back to the battery
2. in a series circuit the value of the current drops with each part

but the voltage remains the same

1. what is the total resistance if the first lightbulb is 4 ohms, the

2nd is 16 ohms, and the 3rd is 20 ohms?

1. referring to the previous example:

if the voltage of the battery is 120 v, what is the current?

Explanation:

Step1: Conventional current direction

Conventional current is defined as flowing from positive to negative. This is a standard convention in electrical circuits.

Step2: Current unit

The unit of current is ampere (amps). Ohms is for resistance and volts is for voltage.

Step3: Resistance unit

The unit of resistance is ohm. Amps is for current and volts is for voltage.

Step4: Ohm's Law

Ohm's Law is \(V = IR\) (Voltage = Current × Resistance). \(I=VR\) is incorrect and \(R/V = I\) can be rewritten from \(V = IR\) but \(V = IR\) is the standard form.

Step5: Circuit requirement

A circuit must be a closed loop for current to flow. So the statement "In order to have a successful circuit you must have a closed loop" is True.

Step6: Voltage drops in series

In a series circuit, the sum of the voltage drops across components equals the battery voltage (from Kirchhoff's Voltage Law). So the statement "The sum of the voltage drops equal back to the battery" is True (assuming proper phrasing intended as sum of voltage drops equals battery voltage).

Step7: Series circuit current and voltage

In a series circuit, the current is the same throughout the circuit (from Kirchhoff's Current Law), and the voltage divides across components. So the statement "In a series circuit the value of the current drops with each part but the voltage remains the same" is False.

Step8: Total resistance in series

For resistors in series \(R_{total}=R_1 + R_2+R_3\). Given \(R_1 = 4\space\Omega\), \(R_2=16\space\Omega\), \(R_3 = 20\space\Omega\), then \(R_{total}=4 + 16+20=40\space\Omega\).

Step9: Current calculation

Using Ohm's Law \(I=\frac{V}{R}\). Given \(V = 120\space V\) and \(R = 40\space\Omega\) (from previous step), then \(I=\frac{120}{40}=3\space A\).

Answer:

1. b. positive to negative
2. b. amps
3. a. ohms
4. c. \(V = IR\)
5. True
6. True
7. False
8. \(40\space\Omega\)
9. \(3\space A\)