Class 5 Maths Chapter 14 How Big? How Heavy? – Complete Notes

📦⚖️ Chapter 14 – How Big? How Heavy?

Class: 5 (CBSE)
Subject: Mathematics
Main Concepts: Volume, Capacity, Cubes, Weight, kg & g

📘 Introduction

In our daily life, we often compare objects by asking: How big is it? and How heavy is it? This chapter helps us understand these ideas using volume and weight.

✔ Volume tells how much space an object occupies.
✔ Weight tells how heavy an object is.

💧 Understanding Volume with Marbles

Sarika took a glass of water and marked the water level as 0. When she dropped marbles into the glass, the water level rose.

Each marble pushes up some water because it takes up space. That space is called the volume of the marble.

✔ Important Observation

More marbles → more water pushed up → more volume

🧪 Measuring Volume Informally

Before using litres or millilitres, we can compare volume using:

Marbles
Coins
Matchboxes
Sand or water

Activity:
Put different objects in water and observe which one pushes up more water.

🥛 Making Your Own Measuring Bottle

Children can make a measuring bottle by:

Marking water level as 0
Adding 5 marbles → mark as 5 M
Adding 5 more marbles → mark as 10 M

This helps understand volume without memorising formulas.

📏 Volume in Millilitres (mL)

Using a measuring bottle, Mollie found that:

$9$ five-rupee coins push up $10$ mL of water

So:

Volume of $6$ marbles ≈ $\dfrac{6}{9} \times 10 = \dfrac{60}{9} \approx 6.7$ mL

📦 How Many Can Fit In? (cm Cubes)

A cube with side $1$ cm is called a centimetre cube.

Volume of $1$ cm cube = $1 \text{ cm}^3$

We can find volume by counting how many cm cubes fit inside an object.

📚 Volume of Math-Magic Book

If the book is:

$l$ cm long
$b$ cm wide
$h$ cm high

Volume = $l \times b \times h$ cm$^3$

📦 Matchbox Play

Matchboxes can be used as equal units to compare volume.

If one matchbox = $10$ cm cubes,
then $56$ matchboxes = $560$ cm cubes

🎲 Making a Paper Cube

When a square paper of side $19.5$ cm is folded, we get a cube of side $7$ cm.

Volume of cube = $7^3 = 343$ cm$^3$

📦 Packing Cubes

Ganesh and Dinga wanted to pack $4000$ cm cubes in boxes.

If one box fits $20 \times 10 \times 6 = 1200$ cubes,
then $3$ boxes fit $3600$ cubes.

So one more box is needed.

🧻 Which Pipe Fills More?

Using the same sheet of paper, different pipes are made.

Even if area is same, volume can be different. The shape matters!

⚖️ Understanding Weight

Weight tells how heavy an object is.

$1$ kg = $1000$ g

🥾 Trek to Gangotri

Students planned food carefully because:

Even one gram extra can make the trek difficult.

Dried food weighs less because water is removed.

🐘 How Heavy Am I?

A blue whale weighs about $35$ times an elephant.

If elephant weighs $5000$ kg,
Blue whale ≈ $35 \times 5000 = 175000$ kg

🏦 Shahid Saves the Bank

Shahid counts coins by weighing them.

Weight of one ₹5 coin = $9$ g
Bag weight = $9000$ g
Number of coins = $\dfrac{9000}{9} = 1000$

✍️ Practice Questions

1) What is volume?

2) Write $2250$ g in kg and g.

3) Find volume of a cube of side $5$ cm.

4) How many ₹5 coins are there in $18$ kg?

5) Why does shape affect volume?

✅ Quick Revision

✔ Volume = space occupied
✔ Weight = heaviness
✔ $1$ kg = $1000$ g
✔ Cube volume = $s^3$
✔ Same area ≠ same volume

🎉 Chapter Complete

After studying this chapter, students can confidently compare volume, measure capacity, calculate cube volume, and understand weight in real-life situations.

Class 5 Maths Worksheet – How Big? How Heavy?

📝 Complete Worksheet – How Big? How Heavy?

Class: 5 (CBSE)
Chapter: How Big? How Heavy?
Main Concepts: Volume, Capacity, Cubes, Weight (kg & g) 🎯

Section A – Multiple Choice Questions (MCQs)

Q1. Volume tells us:

(a) How tall an object is

(b) How heavy an object is

(d) How fast an object moves

Q2. The volume of a cube of side $4$ cm is:

(a) $12$ cm$^3$

(b) $16$ cm$^3$

(d) $8$ cm$^3$

Q3. $1$ kilogram is equal to:

(a) $100$ g

(b) $500$ g

(d) $10$ g

Q4. Which object will push up more water?

(a) Smaller volume object

(b) Larger volume object

(d) Softer object

✔ Q1 → (c) How much space an object occupies
✔ Q2 → (c) $64$ cm$^3$
✔ Q3 → (c) $1000$ g
✔ Q4 → (b) Larger volume object

Section B – Fill in the Blanks

1) Volume is measured in __________ units.

2) $1$ cm cube has volume __________ cm$^3$.

3) $2500$ g = __________ kg __________ g.

4) Formula for volume of a cube = __________.

✔ cubic
✔ $1$
✔ $2$ kg $500$ g
✔ $s^3$

Section C – Very Short Answer Questions

1) What is volume?

2) Write the unit of volume.

3) Write $4500$ g in kg.

✔ Volume is the space occupied by an object.
✔ cm$^3$
✔ $4.5$ kg

Section D – Short Answer Questions

Q1. Find the volume of a cube of side $6$ cm.

Q2. Convert $3$ kg $250$ g into grams.

Q3. Why does a bigger object push up more water?

✔ Volume = $6^3 = 216$ cm$^3$
✔ $3250$ g
✔ Because it occupies more space (greater volume).

Section E – Long Answer Questions

Q1. A cuboid has length $8$ cm, breadth $5$ cm and height $4$ cm. Find its volume.

Q2. Explain the difference between volume and weight with examples.

✔ Volume = $8 \times 5 \times 4 = 160$ cm$^3$
✔ Volume is space occupied (balloon), weight is heaviness (stone).

Section F – HOTS / Thinking Questions ⭐

Q1. Two boxes have the same volume but different shapes. Is it possible? Explain.

Q2. How many cubes of side $1$ cm can fit into a cube of side $5$ cm?

✔ Yes, same volume can have different shapes.
✔ $5^3 = 125$ cubes

🎯 Worksheet Complete

✔ Revise volume & weight formulas
✔ Practice cube problems daily
✔ Understand real-life examples
✔ You are now **exam-ready** ✅