Calculations · 2 min read · HSC Physics

List it. Convert it. Then substitute.

Five moves that bank method marks, even when the final number goes wrong.

1. Step 1 · List

   List every known, in SI unitsWrite each value with its symbol, then convert: mT → T, km → m, MeV → J, nm → m. A missed conversion poisons every line after it.

2. Step 2 · Rearrange

   Rearrange with symbols firstSet up the physics, then do the algebra before a single number goes in. Fewer slips, and the marker can follow your thinking.

3. Step 3 · Substitute

   Show one substitution lineCalculations are marked in steps. One correct substitution is often the first mark, even if the final answer goes wrong.

4. Step 4 · Round once

   Keep every digit. Round once.Carry the full calculator value through every step. Round once, at the end, to the significant figures of the data.

5. Step 5 · Check

   Unit, direction, sense-checkFinish with a unit, and a direction if it’s a vector. Then ask: is that size believable? A radius of 2.5 mm for a fast electron is.

Quick checklist

• Knowns listed in SI
• Symbols before numbers
• One substitution line
• Round once, at the end
• Unit, direction, sense-check

Practise rearranging in CortexHSC

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