Capacity for Class 3

Capacity is an interesting quantity that helps us figure out how much a container can hold. It is something we use every day from the glass of water we drink to the bucket of water we bathe in. In this chapter, we will explore the concept of capacity, understand why it is important and find out how we measure it.

What is Capacity?

Capacity is the maximum amount of a container that can be filled.

When we discuss the capacity of pots, we are determining the amount of water it can hold. Take a close look at the five bottles below:

→ In the first pot, the water level is 0 litre. The pot is empty.

→ In the second pot, the water level is 1 litre. The pot is filled below half.

→ In the third pot, the water level is 2 litres. The pot is filled exactly half. 

→ In the fourth pot, the water level is 3 litres. The pot is filled above half full but not completely full.

→ In the fifth pot, the water level is 4 litres. The pot is filled at maximum capacity.

Capacity is also defined as the maximum amount of liquid a container can hold without any leakage or spillage. It is closely related to volume.

What is Volume?

The term "volume" refers to the amount of space enclosed by the surface of a three-dimensional object. All three-dimensional objects take up a certain amount of space, and this space is expressed in terms of volume.

Capacity Measurement Units

We use liters (L) and milliliters (mL) as the standard units for measuring capacity.

Additionally, other units of capacity include gallons, quarts, and pints.

Conversion of one Unit of Capacity to another

Here are some conversions that help you understand capacity measurements:

→ 1 litre (L) equals 1000 millilitres (mL).

1 L = 1000 mL

→ 1 gallon equals 4 quarts.

1 Gallon = 4 Quarts

→ 1 gallon equals 8 pints.

1 Gallon = 8 Pints

→ 1 quart equals 2 pints.

1 Quarts = 2 Pints

In order to facilitate a better understanding of these measurements, the beaker contains indications for millilitres (mL) and litres (L).

Example 1: What is the capacity of a soup pot in pints if the capacity of the soup in the pot is 16 gallons?

a) 88 Pints
b) 108 Pints
c) 128 Pints
d) 148 Pints

Answer: c) 128 Pints

Explanation: Capacity of the soup in the pot = 16 Gallons
Capacity of the soup in the pot in pints = 16 × 8 Pints
                                                         = 128 Pints

Example 2: The total capacity of all the jars shown below is 10 L 450 mL. The capacity of all the jars is the same. What is the capacity of a jar?

a) 750 mL
b) 850 mL
c) 950 mL
d) 1050 mL

Answer: c) 950 mL

Explanation: Total capacity of all the jars = 10 L 450 mL
= 10 L + 450 mL
= 10 1000 mL + 450 mL
= 10000 mL + 450 mL
= 10450 mL

Capacity of a jar = 10450 mL ÷ 11
                           = 950 mL