**Microscopy: Unit Conversion**

In this section we are going to look at unit conversion between the different lengths.

To go down the list, we multiply by 1000 at each step. For example, if we were converting from micrometre to nanometre, we would multiply by 1000.

To go up the list, we divide by 1000. For example, if we were going from micrometre to millimetre, we would divide by 1000.

Let’s have a few examples.

To go up the list, we divide by 1000. For example, if we were going from micrometre to millimetre, we would divide by 1000.

Let’s have a few examples.

**Example 1**

Convert 6 nanometre to picometre.

In order to convert nanometres to picometres, we multiply by 1000. Therefore, we multiply 6 by 1000.

This tells us that 6 nanometres is 6,000 picometres.

**Example 2**

Convert 7.2 nanometres to micrometres.

In order to convert nanometres to micrometres, we divide by 1000. Therefore, we divide 7.2 by 1000.

This tells us that 7.2 nanometres is 0.0072 micrometres.

**Example 3**

Convert 8.5 mm to nm.

This question is asking us to convert millimetres to nanometres. With this conversion, we are essentially going through two conversion.

We can convert millimetres to micrometres by multiplying by 1000, and then we can convert micrometres to nanometres by multiplying by 1000. Therefore, we can convert millimetres to nanometres by multiplying by 1000 twice.

This tells us that 8.5 mm is 8,500,000 nm.

**End Note**

The different units in the table at the top of this section come up quite a lot and they are fairly easy to forget. Therefore, it is worth getting the table down on a revision card.