Question

What unit is 1000 times smaller than a millimetre?

Answer 1

Hint: We need to know some basics of units for this question. Although we don’t have to solve or do calculations, we are asked to define the unit with respect to another unit compared with 1000 as the unit we need to find must be smaller than the given unit by a thousand times.

Complete step-by-step answer:
In the given question, we are talking about unit that are used to measure different quantities. So, for that in this question we are asked to tell the unit which is thousand times smaller than a unit called millimetre.
Now, to answer this question we will divide 1mm with 1000 that will give us micrometres also called microns. Now, we use these units for the measurements that are very small and we need a smaller scale even than mm.
Hence,
$\begin{align}
  & 1m\div 1000\to 1mm \\
 & \Rightarrow 1mm={{10}^{-3}}m \\
 & 1mm\div 1000=micron=1\times {{10}^{-3}}\times {{10}^{-3}}m \\
\end{align}$
So, from this we can conclude that, $1m\div 1000\div 1000=1micron=1\times {{10}^{-6}}m$
And this is how we got our answer. So, the unit is thousand times smaller than the unit millimetre in micrometres.

Note: In this question, only the unit is asked and accordingly one unit is mentioned so there is no difficulty in solving this. But we must know the arrangement of the basic six units through which we can compare other units whether they are larger or smaller. Also, we can write them in comparison to each other in power raised to 10.