| English | Measurement error |
|---|---|
| Bahasa Melayu | Ralat pengukuran |
| 中文 | 测量误差 |
Definition
The difference between a measured value and the true value of a quantity.
In exam terms
A measurement error is the difference between a measured value and the true value of a quantity. Errors come in two main types: systematic errors, which shift every reading in the same direction (for example a zero error), and random errors, which scatter readings unpredictably (for example parallax).
Systematic errors can be reduced by checking the instrument for a zero error and correcting it; random errors can be reduced by repeating and averaging. A correct sentence: The zero error of the ammeter causes a systematic error in every reading.
Do not confuse error with mistake
Do not confuse a measurement error with a careless mistake. An error is an unavoidable limitation of the instrument or method; a mistake is a blunder such as misreading a scale, and is not counted as an error type.
In Paper 2 you may be asked to state and explain a source of error and how to reduce it. To reduce random error, repeat and take an average; to reduce systematic error, correct the zero error or eliminate parallax by viewing at eye level.
Source: DSKP KSSM Physics Form 4 and 5 (Versi English) (Bahagian Pembangunan Kurikulum (BPK), KPM)