Lesson Notes By Weeks and Term v4 - SHS 3

Lesson Video

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Performance objectives

• Identify the three major arithmetic operations: addition, subtraction, and multiplication.
• Apply these operations in real-world data storage scenarios.
• Analyze how these operations impact data management.
• Reflect on the importance of arithmetic in technology.

Lesson summary

This lesson explores the fundamental actions a computer performs on data. We often think of computers as just storing our files, photos, and music. However, their true power lies in their ability to *manipulate* or change that data. At the heart of this manipulation are basic mathematical calculations called arithmetic operations. In Ghana, we see this every day. When you use a Mobile Money (MoMo) app to send money, the phone's processor performs subtraction on your account balance and addition on the receiver's balance. When a shopkeeper uses a calculator to add up your items, they are using arithmetic operations.

Lesson notes

The Arithmetic Logic Unit (ALU)

The "brain" of a computer is the Central Processing Unit (CPU). Inside the CPU, there is a special component called the Arithmetic Logic Unit (ALU). This is where all the mathematical calculations and logical decisions happen. Arithmetic Unit: This part handles the mathematical operations like addition (+), subtraction (-), multiplication (*), and division (/). Logic Unit: This part handles comparisons and logical decisions, like checking if one number is greater than another (>) or if two values are equal (==).

For this lesson, we are focusing on the Arithmetic Unit. Everything a computer calculates, from the complex graphics in a video game to a simple mobile money transaction, is broken down into millions of these simple arithmetic operations performed by the ALU. Working with Binary

Computers do not understand our decimal number system (base-10). They operate using the binary number system (base-2), which only has two digits: 0 and 1. All data, including numbers, is converted to binary before the ALU can work on it. Decimal (Base-10): 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Binary (Base-2): 0, 1

Evaluation guide

• Discuss 3 major Arithmetic Operations and apply them taking into consideration
• their various functions.
• Group Work/Collaborative Learning:
• Engage in interactive presentations, video analysis, and debates.