Measurement - Measurement of Capacity using Metric Units

Understanding Capacity: Capacity is the measure of how much liquid a container, such as a bottle, bucket, or tank, can hold. Imagine a water bottle filled to the brim; the volume of water inside represents the bottle's capacity.

Metric Units - Litre and Millilitre: In the metric system, we use two main units for capacity. The Litre ($L$) is used for larger quantities like a bucket of water or a carton of milk. The Millilitre ($ml$) is used for very small quantities, such as the liquid in a small spoon or a medicine dropper. Visualize $1 \ L$ as a large water bottle and $1 \ ml$ as a few drops from a pipette.

The Conversion Rule: There is a standard relationship between these units: $1 \ Litre = 1000 \ Millilitres$. This means if you have a $1 \ L$ container, it can hold the same amount as one thousand $1 \ ml$ containers.

Converting Litres to Millilitres: To convert Litres into Millilitres, we multiply the amount by $1000$. For example, a $5 \ L$ jar holds $5 \times 1000 = 5000 \ ml$. This can be visualized as moving the decimal point three places to the right or simply adding three zeros to the end of a whole number.

Converting Millilitres to Litres and Millilitres: When we have a large number of millilitres, we can group them into litres. In a four-digit number like $4520 \ ml$, the digit in the thousands place ($4$) tells us the number of Litres, and the last three digits ($520$) tell us the remaining Millilitres. So, $4520 \ ml = 4 \ L \ 520 \ ml$.

Measuring Tools: We measure capacity using marked containers like measuring cylinders, beakers, or measuring cans. These containers have horizontal lines called 'graduations' on the side. When reading the level, visualize the liquid surface touching a specific mark; that mark indicates the capacity in $ml$ or $L$.

Operations with Capacity: To add or subtract capacities, we arrange the values in columns of $L$ and $ml$. Always ensure the $ml$ part has three digits (e.g., $5 \ ml$ should be written as $005 \ ml$ if needed). We start calculations from the $ml$ side and regroup to the $L$ side if the sum of $ml$ is $1000$ or more.