VOLTAGE AND CURRENT DIVISION LAB REPORT.pdf

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VOLTAGE AND CURRENT DIVISION

Mhlanga S 23721804 and Dlamini L.S 23772727

Experiment Done 13/ 03/ 2013

ABSTRACT ABSTRACT

An expe

An experiment to verify thriment to verify the properties e properties of voltage anof voltage and current divd current division is preseision is presented. The vonted. The voltage dividltage divider er is created using two resistors connected in series in a

is created using two resistors connected in series in a circuit. The current divider is created using 2circuit. The current divider is created using 2 resistors connected in parallel. It is found that if

resistors connected in parallel. It is found that if one of the resistors in one of the resistors in the voltage divider is greater the voltage divider is greater than the other, more voltage will be dropped across it. It

than the other, more voltage will be dropped across it. It is also found that the is also found that the greater the resistor is,greater the resistor is, less current will pass through. Experimental, simulated and calculated results are found to be in good less current will pass through. Experimental, simulated and calculated results are found to be in good

agreement. agreement.

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TABLE OF CONTENTS TABLE OF CONTENTS 1 1.. INTRODUCTION………INTRODUCTION………22 2. 2. _{THEORY………}_{THEORY………}_………_{………..…3,}_{………..…3,}44 3. 3. _{PROCEDURE………}_{PROCEDURE………..………}_..………_………5_………5 4.

4. RESULTS RESULTS AND AND DISCUSSIDISCUSSI_ON………_ON………_………_{………..6,}_{……..6, 7}₇ 5. 5. _{CONCLUSION………}_{CONCLUSION………}_………_………_……….8_.8 6. 6. REFERENCES………REFERENCES……….9…….9 1 1_.. INTRODUCTIONINTRODUCTION

The aim of the lab is to investigate the concepts of voltage and current division. The aim of the lab is to investigate the concepts of voltage and current division.

Voltage and current division is an application of Kirchhoff’s Laws. A voltage divider and a current Voltage and current division is an application of Kirchhoff’s Laws. A voltage divider and a current divider will be designed. In electronics or EET, a voltage divider (also known as a potential divider) is a divider will be designed. In electronics or EET, a voltage divider (also known as a potential divider) is a linear circuit that produces an output voltage (V

linear circuit that produces an output voltage (Voutout) that is a f) that is a fraction of its input voltage (Vraction of its input voltage (Vinin). Voltage). Voltage

division refers to the partitioning of a voltage among the

division refers to the partitioning of a voltage among the componencomponents of the ts of the divider. a current divider isdivider. a current divider is a simple linear circuit that produces an outp

a simple linear circuit that produces an output current (IX) that is a fut current (IX) that is a fraction of its input current (IT).raction of its input current (IT). Current division refers to the splitting of

Current division refers to the splitting of current between the branchecurrent between the branches of s of the divider. The currents inthe divider. The currents in the various branches of such a circuit will always divide in such a way as to minimize the total energy the various branches of such a circuit will always divide in such a way as to minimize the total energy expended [1]. In this experiment the voltage and current division properties will be verified. Slight expended [1]. In this experiment the voltage and current division properties will be verified. Slight deviations are caused by experimental errors which include taking somewhat wrong readings due to deviations are caused by experimental errors which include taking somewhat wrong readings due to fluctuating values in the ammeter

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3 3 2. THEORY

2. THEORY

Voltage and current division allow us to simplify the task of

Voltage and current division allow us to simplify the task of analysinanalysing a circuit.g a circuit. Voltage Division allo

Voltage Division allows us to calculate what fraction of ws us to calculate what fraction of the total voltage across a series stringthe total voltage across a series string of resistors is

of resistors is dropped across any one resistor dropped across any one resistor ..

..

For the circuit of

For the circuit of Fig.1 voltage division formulas are:Fig.1 voltage division formulas are:

S S V V R R R R R R )) (( 11 22 1 1     1 1 V V (1)(1) S S V V R R R R R R )) (( 11 22 2 2     2 2 V V (2)(2) Where V is the

Where V is the voltage and R is the resistancevoltage and R is the resistance

Figure.1 Voltage divide

Figure.1 Voltage divider circuit [2]. r circuit [2]. Used to measure what fraction of Used to measure what fraction of the total voltage isthe total voltage is dropped across any one resistor.

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Current Division allow

Current Division allows us to s us to calculate what fraction of the total current calculate what fraction of the total current into a parallel string of into a parallel string of resistorsresistors flows through any one of the resistors.

flows through any one of the resistors. For the circuit of

For the circuit of Fig.2 current division formulas are:Fig.2 current division formulas are:

S S I I R R R R R R )) (( 11 22 2 2     1 1 II (3)(3) S S I I R R R R R R )) (( 11 22 1 1     2 2 II (4)(4) Where I is

Where I is the current and R is the resistancethe current and R is the resistance

Figure.2 Current Divider circuit [2] Figure.2 Current Divider circuit [2]

Current divider circuit used to calculate what fraction of the total

Current divider circuit used to calculate what fraction of the total current into a parallel string of current into a parallel string of resistors flows through any one of the resistors.

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5 5 3. PROCEDURE 3. PROCEDURE 3.1 Voltage Division 3.1 Voltage Division

The circuit was constructed as shown in Figure 3. The voltages v1 and v2 were measured by choosing The circuit was constructed as shown in Figure 3. The voltages v1 and v2 were measured by choosing R1

R1 = 5.6 KΩ, R2 = 1.5 KΩ a= 5.6 KΩ, R2 = 1.5 KΩ and setting the variable power supply voltage Vs = 5V.nd setting the variable power supply voltage Vs = 5V. This step was repeated for R1 =

This step was repeated for R1 = R2 = 5.6 KΩ and the measureR2 = 5.6 KΩ and the measurements were noted down. The voltagesments were noted down. The voltages V1 and V2 were calculated by using the formulas (1) and (2) in each case.

V1 and V2 were calculated by using the formulas (1) and (2) in each case.

Figure.3 Voltage divider circuit [2] Figure.3 Voltage divider circuit [2]

3.2 Current division 3.2 Current division A circuit was

A circuit was constructed aconstructed as shown in s shown in figure 2. The currenfigure 2. The currents Is, I1 and I2 ts Is, I1 and I2 were measuwere measured by chored by choosingosing R1 = 2.2 KΩ, R2 = 5.6 KΩ a

R1 = 2.2 KΩ, R2 = 5.6 KΩ and Rs=1 KΩ .The variable power supply voltage was set atnd Rs=1 KΩ .The variable power supply voltage was set at Vs=10 V. This s

Vs=10 V. This step was repeated by using R1=R2 =2.2 KΩ and the measurements were noted down.tep was repeated by using R1=R2 =2.2 KΩ and the measurements were noted down.

Figure.4 Current divider circuit [2] Figure.4 Current divider circuit [2]

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4. RESULTS AND DISCUSSION 4. RESULTS AND DISCUSSION

4.1 Voltage Division Results 4.1 Voltage Division Results

Tables 4.1, 4.2 and 4.3 show the calculated, simulated and experimental results. Tables 4.1, 4.2 and 4.3 show the calculated, simulated and experimental results. Table 4.1 Calculated results

Table 4.1 Calculated results R(KΩ) R(KΩ) VV11(v) (v) VV22(v)(v) R1=5.6, R1=5.6, R2=1.5 R2=1.5 3.94 3.94 1.061.06 R1=5.6, R1=5.6, R1=5.6 R1=5.6 2.50 2.50 2.502.50 Table 4.2 Simulated results

Table 4.2 Simulated results R(KΩ) R(KΩ) VV22(v) (v) VV22(v)(v) R1=5.6, R1=5.6, R2=1.5 R2=1.5 3.94 3.94 1.061.06 R1=5.6, R1=5.6, R1=5.6 R1=5.6 2.50 2.50 2.502.50 Table 4.3 Experimental results

Table 4.3 Experimental results R(KΩ) R(KΩ) VV11(v) (v) VV22(v)(v) R1=5.6, R1=5.6, R2=1.5 R2=1.5 3.98 3.98 1.061.06 R1=5.6, R1=5.6, R2=5.6 R2=5.6 2.51 2.51 2.532.53

The voltage results convincingly seem to be in good agreement. The tables clearly indicate that the The voltage results convincingly seem to be in good agreement. The tables clearly indicate that the calculated and simulated results were found to be the same. Slight deviations in the experimental calculated and simulated results were found to be the same. Slight deviations in the experimental results might have been caused by fluctuating values in the ammeter making it hard

results might have been caused by fluctuating values in the ammeter making it hard to read preciseto read precise values. In addition, setting the voltmeter to exactly 10V on the Digital Lab also proved to be a difficult values. In addition, setting the voltmeter to exactly 10V on the Digital Lab also proved to be a difficult task because the knob was too sensitive. If this experiment is to be redone, improvements can be task because the knob was too sensitive. If this experiment is to be redone, improvements can be

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4.2 Current Division Results 4.2 Current Division Results

Tables 4.4, 4.5 and 4.6 show the calculated, simulated and experimental results. Tables 4.4, 4.5 and 4.6 show the calculated, simulated and experimental results. Table 4.4 Calculated Results

Table 4.4 Calculated Results R(

R(Ω)Ω) IIss(mA) (mA) II11(mA) (mA) II22(mA)(mA)

R1=1,

R1=1, R2=2.2, R2=2.2, R3=5.6 R3=5.6 3.88 3.88 2.79 2.79 1.091.09 R1=1,

R1=1, R2=2.2, R2=2.2, R3=2.2 R3=2.2 4.76 4.76 2.38 2.38 2.382.38 Table 4.5 Simulated results

Table 4.5 Simulated results R(

R1=1

R1=1 , , R2=2.2 R2=2.2 , , R3=5.6 R3=5.6 3.88 3.88 2.79 2.79 1.091.09 R1=1,

R1=1, R2=2.2, R2=2.2, R3=2.2 R3=2.2 4.76 4.76 2.38 2.38 2.382.38 Table 4.6 experimental results

Table 4.6 experimental results R(

R1=1,

R1=1, R2=2.2, R2=2.2, R3=5.6 R3=5.6 3.89 3.89 2.79 2.79 1.101.10 R1=1,

R1=1, R2=2.2, R2=2.2, R3=2.2 R3=2.2 4.81 4.81 2.42 2.42 2.392.39

The calculated, simulated and experimental current results are also in convincing compliance. The The calculated, simulated and experimental current results are also in convincing compliance. The calculated and simulated results gave out corresponding values. On the other hand the experimental calculated and simulated results gave out corresponding values. On the other hand the experimental results proved to be somewhat different from the calculated and simulated results. This might have results proved to be somewhat different from the calculated and simulated results. This might have been caused by the fact that the ammeter that was used to measure the current would slightly alter the been caused by the fact that the ammeter that was used to measure the current would slightly alter the values making it very possible to take wrong readings. If the experiment is to be redone, improvements values making it very possible to take wrong readings. If the experiment is to be redone, improvements can be made by allowing the ammeter to settle to one value before taking readings to avoid taking can be made by allowing the ammeter to settle to one value before taking readings to avoid taking wrong reasons.

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5. CONCLUSION 5. CONCLUSION

An expe

An experiment to verify thriment to verify the properties e properties of voltage anof voltage and current divid current division was pression was presented. The vented. The voltageoltage divider was created using two resistors connected in series in a circuit. The

divider was created using two resistors connected in series in a circuit. The current divider was createdcurrent divider was created using 2 resistors connected in parallel. It was found that if

using 2 resistors connected in parallel. It was found that if one of the resistors in one of the resistors in the voltage divider the voltage divider was greater than the other, more voltage was dropped across it.

was greater than the other, more voltage was dropped across it. It was also found that the It was also found that the greater thegreater the resistor was, less current

resistor was, less current passed through. Experimentapassed through. Experimental, simulated and calculated results were l, simulated and calculated results were foundfound to be in good agreement. Slight deviations were caused by experimental errors which included taking to be in good agreement. Slight deviations were caused by experimental errors which included taking somewhat wrong readings due to fluctuating values in the ammeter and voltmeter.

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9 9 6. REFERENCES

6. REFERENCES

[1]

[1] http://en.wihttp://en.wikipedia.org/wikipedia.org/wiki/Voltage_dki/Voltage_divider ivider

[2] Circuit drawings taken from Electronics Laboratory Manual [2] Circuit drawings taken from Electronics Laboratory Manual http://www.wisc-online.com/Objects/ViewObject.aspx?ID=DCE3502