Calculation Technique in Physics

Physics is a quantitative subject, and calculations typically account for around 40% of the marks across all three papers. The difference between a good grade and a great grade often comes down to calculation technique — not whether you can solve the problem, but whether you present your solution in a way that earns every available mark.

---

The Golden Rule: Show Your Working

Every calculation in physics should follow this structure:

1. Write the equation you intend to use (in symbol form)
2. Substitute values with units into the equation
3. Rearrange if necessary (you can rearrange before or after substituting — do whichever feels more natural)
4. Calculate and present your answer
5. Include units in your final answer
6. Round to an appropriate number of significant figures

This structure is essential because examiners award method marks as well as answer marks. If you make an arithmetic error but your method is clearly correct, you will still earn method marks. If you only write the final answer and it is wrong, you score zero.

---

Rearranging Equations

Many students lose marks because they cannot rearrange equations confidently. Practise rearranging the key equations from your equation sheet: