1. Experiment No. 1 Ohm’s Law
Electrical Engineering Department
Third Year E/C
Digital Electronic Circuits
Experiment No. 1
Ohm’s Law
Prepared by:
Diary R. Sulaiman
2018
Prepared by: Diary R. Sulaiman

2. Contents - Introduction - Basic Defitions - Electrical meters - Electrical Power supplu - Connections and facilities - Results -Remarks
Prepared by: Diary R. Sulaiman 2

3. All electrical circuits require three elements.
A voltage source , that is,
a battery or power supply. + -
(2) A conductor to carry electrons
from and to the voltage
source The conductor is often a wire.
(3) A resistance or Load.
A point where energy is extracted
form the circuit in the form of heat, light, motion, etc.

4. In electrical circuits, Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference or voltage across the two points, and inversely proportional to the resistance between them
I= V / R

5. All electrical circuits require three elements.
A voltage source, a battery or power supply.
(2) A conductor to carry electrons from and to the voltage
Source, The conductor is often a wire.
(3) A resistance or LOAD. A point where energy is extracted
form the circuit in the form of heat, light, motion, etc.

6. Potential Rise Across a Power Source
volts
current
current
Battery
Electrons have
More Energy
Electrons have
Less Energy
Electrons get
An energy boost

7. Potential Drop Across a Resistor
volts
current
Resistor
Electrons have
Less Energy
Electrons have
More Energy
Energy is lost
In the resistor

8. (1) VOLTMETER – MEASURES THE IT IS MEASURED IN VOLTS (V, mV,…))
measuring devices
OR METERS
(1) VOLTMETER – MEASURES THE IT IS MEASURED IN VOLTS (V, mV,…))
(2) AMMETER–.IT IS MEASURES IN CURRENT (A, mA,..)
(3) OHMETER– IT IS MEASURES RESISTANCE (, k, m, …)
(4) MULTIMETER– MEASURED ALL THESE QUANTITIES. M A O V

9. Electrical Meters volts AMPS Voltmeters measure potential in volts
Ammeters measure
current in amperes
and are always
wired in series in
the circuit.
AMPS
Voltmeters measure
potential in volts
and are always
wired in parallel
in the circuit.
volts

10. CONNECTION OF Meters AMMETER: is connected in series, while
VOLTMETER: is connected in parallel

11. An actual meter

12. Electrical Symbols A V battery + - AC generator wiring voltmeter
ammeter A
Variable
resistance
resistance

13. figure 1 PROCEDURE Connect the circuit shown in figure 1.
Have the instructor inspect your circuit before applying power.
Slowly increase the voltage across the resistor from 0V to 10V in approximately 1V increments. Record the measured voltages and currents from your multimeter as in table 1.
V (Volts)
I (mA)
Fig.1
Fig.2
Fig.3 1 2 3 4 5 6 7 8 9 10
figure 1