Lesson Notes By Weeks and Term v4 - SHS 3
ALTERNATING CURRENT
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ALTERNATING CURRENT
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Subject: Physics
Class: SHS 3
Term: 2nd Term
Week: 7
Grade code: 3.3.2.LI.3
Strand code: 3
Sub-strand code: 2
Content standard code: 3.3.2.CS.1
Indicator code: 3.3.2.LI.3
Theme: ELECTRIC FIELD, MAGNETIC FIELD AND ELECTRONICS
Subtheme: ALTERNATING CURRENT
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As a starting point, we will have a brief class discussion. The electricity we get from the Electricity Company of Ghana (ECG) that powers our homes, schools, and businesses is different from the electricity we get from a battery in a remote control or a torchlight. The battery provides Direct Current (DC), which flows in one direction only. The electricity from ECG is Alternating Current (AC), which constantly changes direction. Understanding AC is crucial because it's the backbone of our national power grid and runs almost every major appliance we use, from the fan in our classroom to the corn mill in the community.
(35 minutes)
This section is the core content delivery. The teacher will explain using the board, charts, and interactive questioning. Part 1: Defining Alternating Current (AC) and Voltage (AV)
First, let's recall Direct Current (DC). This is the current from a battery. It flows in only one direction, and its value is constant. Graph of DC: A straight horizontal line.
Now, Alternating Current (AC) is a current that periodically reverses its direction and continuously changes its magnitude. It follows the pattern of a sine wave. The same applies to Alternating Voltage (AV). Graph of AC: A sinusoidal wave.