PRACTICAL # 04Verification of OHM’s law

By: Engr.Irshad Rahim Memon

Objective of this practical is to verify that voltage applied to a closed resistive path is equal to the product of current flowing through and resistance of that path

OBJECTIVE:

Few resistors bread board multimeter variable DC power supply connecting wires etc

Required Apparatus:-

Ohm’s law states that current through a closed resistive path is directly proportional to applied voltage, where resistance of path is kept constant.

Ohm experimentally determined that if the voltage across resistor is increased, current through resistor will also increase as shown in figure 01.

Introduction

Fig01Figure 01: Ohm law for constant resistance (a) less voltage, less current (b) more voltage, more current

Ohm also determined if voltage is kept constant then less resistance results in more current and more resistance results in less current as shown in figure 02

Continued…..

Figure 02: Ohm law for constant voltage (a) less resistance, more current (b) more resistance, less current

Figure02

Ohm also determined if voltage is kept constant then less resistance results in more current and more resistance results in less current as shown in figure 02.

Continued…..

Ohm’s law can be formulated as follows:

Continued….

Connect a variable voltage source, a resistor and an ammeter in series as shown in figure 03(a) to verify direct relationship between voltage and current as shown in figure 03(c)

Procedure:-

Verification of Ohm’s law for constant resistance (a) circuit (b) different values of current for different values of voltage (c) graphical relation between voltage and current

Figure03

Also connect a variable resistor, a voltage source and an ammeter in series as shown in figure 04(a) to verify inverse relationship between resistance and current as shown in figure 04(c)

Continued….

It is observed that current varies directly with applied voltage where resistance is kept constant. It is also observed that current varies inversely with resistance where applied voltage is kept constant.

Observation:-.

Fill the missing quantity in the table 01 with the help of Ohm’s law.

Table to fill

S.No R (Ohm) I (Ampere) V (volt)

Example 1K 2 2K

1 5M 100

2 100 50

3 0.05 m 1

ANY QUERY

THANKS

PRACTICAL # 05Verification of Kirchhoff’s Voltage Law (KVL)

By: Engr.Irshad Rahim Memon

Objective of this practical is to verify KVL.

OBJECTIVE

Few resistors bread board multimeter variable DC power supply connecting wires etc

Required Apparatus:-

Kirchhoff’s voltage law states that “sum of all the voltage drops around a single closed path in a circuit is equal to the total source voltage in that loop” or it can also be defined as “The algebraic sum of all the voltages (both source and drop) around a single closed path is equal to zero” as shown in figure 01.

Theory:

Figure 01: Demonstration of KVL

Figure01

KVL may be formulated as follows.

Continued….

Vs=V1+V2+V3+…+Vn orVs-V1-V2-V3-…-Vn=0

For the verification of KVL, a simple series resistive circuit like shown in figure 01 should be prepared.

Procedure

KVL is verified KVL law is verified for series circuit of three

resistors of known values connected in series. Results are given in table 01.

Observation

Table 1

S.No Vs VR1 VR2 VR3 Vs= VR1 +VR2 +VR3

example 10Volt 2 Volt 3 Volt 5 Volt 10 Volt=2+3+5 Volt

1 5Volt

2 15volt

3 20volt

ANY QUERY

PRACTICAL # 06Verification of Kirchhoff’s Current Law (KCL)

By: Engr.Irshad Rahim Memon

Objective of this practical is to verify KCL.

OBJECTIVE

Few resistors bread board multimeter variable DC power supply connecting wires etc

Required Apparatus:-

Kirchhoff’s current law states that “Algebraic sum of all currents entering and leaving a node is equal to zero” as demonstrated in figure 01.

Theory:

Figure 01: Demonstration of KCL

Figure01

For the verification of KCL, a simple parallel resistive circuit like shown in figure 02 should be prepared.

Procedure:

Figure 02: Verification of KCL

Figure 02

KCL law is verified for parallel circuit of three resistors of known values connected in parallel. Results are given in table 01.

Continued….

Table 01

S.No Itotal IR1 IR2 IR3 Itotal = IR1 +IR2 +IR3

example 1Amp 0.5 Amp 0.3 Amp 0.2 Amp 1Amp=0.5+0.3+0.2 Amp

1 0.5 Amp

2 0.25 Amp

3 0.1 Amp

ANY QUERY