### Distance & Volume

- Rulers can be used to measure small distances of a few cm. They are able to measure to the nearest mm

*A ruler can measure small distances to the nearest mm*

- When measuring larger distances (of a few metres) a tape measure is more appropriate or, when measuring even larger distances, a trundle wheel

*Trundle wheels can be used to measure large distances*

### Micrometer Screw Gauge

### Time

- Stop-clocks and stopwatches can be used to measure time intervals
- An important factor when measuring time intervals is human reaction time. This can have a significant impact upon measurements when the measurements involved are very short (less than a second)

### Multiple Readings

- Suppose you have to measure the thickness of a sheet of paper. The thing that you are trying to measure is so small that it would be very difficult to get an accurate answer
- If, however, you measure the thickness of 100 sheets of paper you can do so much more accurately. Dividing your answer by 100 will then give an accurate figure for the thickness of one sheet
- This process of taking a reading of a large number of values and then dividing by the number, is a good way of getting accurate values for small figures, including (for example) the time period of a pendulum – measure the time taken for 10 swings and then divide that time by 10