Circuit lab 4 verification of ohm's law@taj . This lecture is from my class lectures in IIT-JU. . Find me: Website: https://www.tajimiitju.blogspot.com Linked in: https://www.linkedin.com/in/tajimiitju Researchgate: https://www.researchgate.net/profile/Tajim_Md_Niamat_Ullah_Akhund Youtube: https://www.youtube.com/tajimiitju?sub_confirmation=1 Slideshare: https://www.slideshare.net/TajimMdNiamatUllahAk Facebook: https://www.facebook.com/tajim.mohammad Gitlab: https://gitlab.com/users/tajimiitju Google+: plus.google.com/+tajimiitju Email: tajim.mohammad.3@gmail.com Twitter: https://twitter.com/Tajim53

1. Electronic Devices and
Circuits LAB (IT-1106)
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2. Experiment 4
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Purpose/Objective:
In this lab, you will verify Ohms Law
for four different resistors. You will
measure the true resistance of each
resistor and the voltage applied to
each resistor. You will then calculate
the predicted current through each
resistor. Finally, you will measure
the actual current through each
resistor to verify (or disprove!)
Ohm’s Law.

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Theory

5. 1. One regulated variable Power Supply
(0-30 V)
2. Two Digital Multi-meter (One DC mili-
ammeter, one DC voltmeter)
3. Circuit Experiment Board (Breadboard)
4. Resistors (10KΩ, 5KΩ and 1KΩ)
5. Connecting Wires
6. Cutting tools etc.
What we need
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Cautions:
This equipment is delicate. Everything
should go together with the lightest of
touches. Do not force anything!

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The circuit diagram to verify Ohm’s law is
shown below:

8. 1. Construct the circuit on the breadboard, as shown in the above figure
(amammeter, a resistor are in series with a regulated power supply and a
voltmeter is in parallel to the resistor).
2. Start the experiment from the zero voltage of the power supply. For
zero supply voltage, the current flow is zero. Now increase the supply
voltage from 0 to 20 V in at least ten steps, take the ammeter and
voltmeter readings.
3. By using equation (1), find the value of R for each reading. Observe
that the value of R must be constant for each reading, which verifies Ohm’s
law.
4. Plot a graph of I as a function of V (I in Y-axis and V in X-axis) with the
above readings. The graph should fit a straight line passing through the
origin. The slope of this line will indicate the resistance of the resistor.
5. Compare the experimental resistance value with the color coded value
and direct ohmmeter reading.
Procedure
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References:
1. Wikipedia
2. KMA sir’s lecture

13. LAB Report
1. LAB report must
be hand written.
2. Report on today’s
LAB must be
submitted on next
class individually.
3. LAB report will
contain: topic, brief
description of the
topic, circuit
diagram, procedure,
data table,
equipment list and
graph.
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