Calculation Techniques for Physics

Calculations make up a significant proportion of the marks on both Edexcel GCSE Physics (1PH0) papers — approximately 30% of all marks require mathematical skills. This lesson covers the essential techniques you need to maximise your marks on calculation questions.

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The Four-Step Method

Every calculation in physics should follow this method:

Step	Action	Why It Matters
1	Write the equation	Shows the examiner which equation you are using (earns a mark)
2	Substitute the values	Shows you can identify the correct quantities
3	Calculate	Perform the arithmetic
4	State the answer with units	A missing unit can lose you a mark

Worked Example

Calculate the weight of an object with a mass of 75 kg. (gravitational field strength g = 9.8 N/kg)

Step 1: W = mg

Step 2: W = 75 × 9.8

Step 3: W = 735

Step 4: W = 735 N