Notes on Order of Magnitude

Introduction

• Objective: Understand the concept of order of magnitude and how to perform related calculations.
• Context: Used to compare approximate sizes of different objects.

Definition of Order of Magnitude

• Order of Magnitude: A way to express the size relationship of objects using powers of ten.
• One Order of Magnitude: 10 times larger than another object.

Examples of Order of Magnitude

• Apple and Orange: Approximately the same size, hence same order of magnitude.
• Pineapple vs. Lemon:
  • Pineapple is about 10 times larger than the lemon.
  • Therefore, it is one order of magnitude larger.
• Dog vs. Woodlouse:
  • Dog is about 100 times longer than a woodlouse.
  • Hence, dog is two orders of magnitude longer.

Calculating Order of Magnitude

• Key Idea: Each order of magnitude is 10 times greater.
• Method: Count the number of zeros in the multiplier.
  • 10 times: 1 order of magnitude.
  • 100 times: 2 orders of magnitude.
  • 1,000 times: 3 orders of magnitude.

Example Problem

• Problem: A fox is 40 cm long, and a tick on the fox is 0.4 cm long.
• Solution Steps:
  1. Divide 40 by 0.4, which equals 100.
  2. Recognize that 100 has two zeros.
  3. Therefore, the fox is two orders of magnitude longer than the tick.

Additional Resources

• Practice Questions: Available in the accompanying workbook, accessible via the provided link.

Conclusion

• Skills Gained: Ability to describe and calculate orders of magnitude.
• Application: Useful for comparing sizes in scientific contexts.

Note: These notes are based on the Free Science Lessons video on order of magnitude calculations.