Binary Sneeze

OBJECT:

• To verify Kirchoff’s Current Law (KCL)
• To verify Current Divider Rule (CDR)

EQUIPMENT:

• DC power supply (0-30V)
• DMM
• Resistors of different values
• Connecting wires
• Digital Experiment Board

THEORY:

KCL states that:

“The sum of currents flowing into a point in a circuit is equal to the sum of the currents flowing out of that same point”

CIRCUIT DIAGRAM:

PROCEDURE:

Steps to Prove KCL:

• Select the three resistors.
• Measure all the resistances using multimeter and verify using the color codes.
• Make the circuit as shown in the diagram.
• Measure the current I_A, I_B, I_C across the three resistors using multimeter.
• Verify KCL by the following equation:

I= I_A +I_B +I_C

Verification of Current Divider Rule:

• Set the apparatus as shown in the circuit diagram.
• Set the voltage V = 10 volts by the power supply and keep it constant during the whole experiment.
• Measure the currents I_A, I_B, I_C across the three resistances using DMM.
• Verify the Current Divider Rule by using the formulae:

I_A = (1/RA) *I / (1/R_A+1/R_B+1/R_C)

I_B = (1/RB)*I / (1/R_A +1/R_B +1/R_C)

I_{C =} (1/RC)*I / (1/R_A + 1/R_B + 1/R_C)

OBSERVATIONS AND CALCULATIONS:

For values of Resistance:

For values of Current:

V=1V

So,

I_A= (28.1/1) mA =28.1mA

I_B= (9.5/1) mA   = 9.5 mA

I_C= (4.3/1) mA  = 4.3 mA

RESULT:

• Total current measured by multimeter =I = I_A+I_B+I_C =41.1mA=0.041A.
• Total current measured manually = I = I_A+I_B+I_C =0.0419A.

• Both of the above results show that, Sum of the current flowing into a point in a circle is equal to the sum of the currents flowing out of that same point.

• The table for values of voltage verifies Current Divider Rule.

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