# A student is setting up equipment for an experiment and needs to convert between SI units and their prefixes. The student records a current of 0.045 A, a frequency of 3 500 000 Hz, a length of 0.000 012 m, a time of 0.000 000 250 s, and a mass of 6 200 g. Express each measurement using an appropriate SI prefix, giving the correct prefix symbol in each case.

> AQA A-Level Physics (7408) — 3.1.1 Use of SI Units and Their Prefixes · State · 5 marks

## Mark scheme (5 marks)

1. Current: 45 mA (milliamps / milliamperes)
2. Frequency: 3.5 MHz (megahertz)
3. Length: 12 μm (micrometres)
4. Time: 250 ns (nanoseconds)
5. Mass: 6.2 kg (kilograms)

## Key terms

- [SI units](https://www.gradenine.co.uk/glossary/si-units)
- [prefix](https://www.gradenine.co.uk/glossary/prefix)

## Related

- [Revision notes for AQA A-Level Physics (7408)](https://www.gradenine.co.uk/learn)
- [How to answer "State" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/a-student-is-setting-up-equipment-11e53ca9) · Published by Druglandscape Ltd.