Learning Objectives

• To learn how to make estimates

• How to use orders of magnitude.

• Use concepts to recognise whether answers are reasonable.

• Carry out back of the envelope calculations.

Syllabus Statements

• Orders of magnitude

• Estimate of approximate values for physical quantities;

Key Questions

• What is the point of making estimates?

• Why do we make comparisons?

• What are orders of magnitude?

Key Words

Estimate, comparison, order of magnitude, scale, size