Term: 2^{nd} Term
Week: 7
Class: Senior Secondary School 1
Age: 15 years
Duration: 40 minutes of 5 periods each
Date:
Subject: Physics
Topic: Verification of Ohm’s law(Practical)
SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to
INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, videos from source
INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures
INSTRUCTIONAL PROCEDURES
PERIOD 12
PRESENTATION 
TEACHER’S ACTIVITY 
STUDENT’S ACTIVITY 
STEP 1 INTRODUCTION 
The teacher reviews the previous lesson on Ohm’s law 
Students pay attention 
STEP 2 EXPLANATION 
He solves some exercises on workdone and power

Students pay attention and participates 
STEP 3 DEMONSTRATION 
He explains and carries out an experiment to verify the ohms law

Students pay attention and participate 
STEP 4 NOTE TAKING 
The teacher writes a summarized note on the board 
The students copy the note in their books 
NOTE
VERIFICATION OF OHM’S LAW
The ammeter which measures the current flowing through the metallic conductor (Constant wire) is connected in series with the wire and the cell. The voltmeter is connected in parallel with the conductor and measures the p.d. across it. The rheostat is used to vary the current flowing in the circuit.
We cause the current to flow by pressing down the switch. The graph of V against I is plotted and a straight line graph passing through the origin is observed. The slope gives the resistance of the wire.
Graph of Voltage (V) against Current (I)
Slope (S) = ΔπΔπΌ = π2− π1πΌ2− πΌ1
Slope (S) = Resistance (R).
WORK DONE IN ELECTRIC CIRCUIT/ ELECTRICAL ENERGY
Work done when electricity flows from one point to another of different potential is given by
W= QV
The Unit is Joule = Coulomb x Volt
Since Q = It
Therefore, W= QV = IVt
From ohms law, V= IR
:. W= QV
R
ELECTRICAL POWER
Power (P) is define the time rate of doing work.
P = ππππππππ/πΈπππππ¦ πππ π ππππ‘π(π½ππ’πππ )
ππππ π‘ππππ (πππππππ )
Electrical power is the amount of electrical work done or electrical energy dissipated per second.
P = IVt
t
Therefore, P= IV
Power P = IV = I^{2}R = V^{2}
^{ }R
Unit of power is Watt (W).
Large units of power are kilowatt (KW) and Megawatt (MW)
1kw = 1000 watts
1MW=10^{6}W=10^{3}KW
Example: Calculate the Electrical energy and Power Used by an electric Heater of 11β¦ when the voltage source is 220V ac source for 2seconds
Solution:
Resistance R = 11β¦
Voltage V = 220V
Time t = 2s
Electrical energy =
= 220^{2} x 2
11
= 8800J = 8.8KJ
Power = ππππππππ / πΈπππππ¦
ππππ π‘ππππ
= π^{2}
π
= 8800
2
= 4400w
= 4.4KW
PRACTICAL
VERIFICATION OF OHM’S LAW USING STANDARD RESISTOR (2Ω), AMMETER (02A), CONNECTING WIRES AND VOLTMETER.
MATERIALS REQUIRED :
A resistor of about 5 Ω,
an ammeter ( 0  3 A),
a voltmeter (0  10 V),
four dry cells of 1.5 V each with a cell holder (or a battery eliminator),
a plug key,
connecting wires,
and a piece of sand paper.
PRECAUTIONS :
CIRCUIT DIAGRAM:
PROCEDURE :
OBSERVATIONS:
Observation from graph:
Observation table:
As performed in the simulator:
EVALUATION: 1. A box is pulled with a force of 25N to produce a displacement of 15m. If the angle between the force and displacement is 30Λ, find the work done by the force.
CLASSWORK: As in evaluation
CONCLUSION: The teacher commends the students positively