Resistors in Series and Parallel

Group No. 1

Date Performed: October 12, 2009 Date Submitted: October 12, 2009 Year & Section: 2E Course: Medical Technology

ABESAMIS, Maria Feliza ACOSTA, Marie Em Clarisse AGUSTIN, Francheska AQUITANIA, Mary Christelle BAGSICAN, Marilu Jane BERNAS, Michael Bryan Experiment no. 15

RESISTORS IN SERIES AND PARALLEL I.

Abstract

A resistor is a component of an electrical circuit that resists the flow of electrical current. It has two terminals across which electricity must pass, and is designed to drop the voltage of the current as it flows from one terminal to the next. It is primarily used to create and maintain a known safe current within an electrical component. In this experiment, the resistance and the tolerance of each resistor was read using the color bands. The values from the readings were compared with the readings of the digital multimeter.

II. Guide Questions

1. How does the total resistance compare with the individual resistances in a series circuit?

In a series circuit, the sum of the Total resistance is always greater than the individual resistance of the resistor.

2. How does the total resistance compare with the individual resistances in the parallel circuit In a parallel circuit, the sum of the total resistance is always less than the individual resistance of the resistor.

3. Given three resistors: 50 Ω , 100Ω , 200Ω . What is their total resistance when they are connected in (a) series and (b) in parallel?

a) Series: RT = R1 + R2 +R3 . . . RT = 500 Ω + 100 Ω + 200 Ω RT = 350 Ω b) Parallel: RT = [R1-1 + R2

-1

RT = [500 Ω

+ 100 Ω

-1

+R3-1]

-1

-1

+ 200 Ω 1]

-1

RT = 28.57 Ω 4. Given three resistors: 1500 Ω , 50 Ω , and 100 Ω . How should these be connected so that the total resistance is 136 Ω ? R1 = 1500 Ω

R2 = 50 Ω

R3 = 100 Ω

R2R3 = 50 Ω + 150 Ω R2R3 = 150 Ω

R1 = 1500 Ω

R2R3 = 150 Ω RT = [R2-1 + R3-1]

-1

RT = [1500-1 + 150-1]-1 RT = 136.36 Ω RT = 136 Ω

III. Results:

Table 1 Resistance of each resistor Resistor

Color Code Reading

R1

Brown, Black, Brown, Gold 100 Ω Red, Red, Brown, Gold

R2 R3

220 Ω Brown, Green, Red, Gold 1500 Ω

Table 2 Resistors in Series

Multimeter Reading 100 Ω

Color Code Tolerance 95 to 105 Ω

222.9 Ω

209 to 231 Ω

1487 Ω

1425 to 1575 Ω

Total Resistance Resistors

Color Code

R1R2R3

1820 Ω

Multimeter Reading 1809 Ω

Tolerance 1729 to 1911 Ω

Table 3 Resistors in Parallel

Total Resistance Resistors R1R2R3

Color Code 65.74 Ω

Multimeter Reading 69 Ω

IV. References WEBSITE:

Resistor http://www.wisegeek.com/what-is-a-resistor.htm Retrieved: October 19, 2009

Tolerance 62.45 to 69.02 Ω