✨ For very large distances (like the length of a railway track between two cities), we use 🟩 kilometres (km).

✨ For very small lengths (like the thickness of a page), we use 🟦 millimetres (mm).

👉 Example:
🚄 Distance between Jaipur and Delhi = about 🔵 270 km
📖 Thickness of a notebook page = about 🟣 0.1 mm

They help travellers know how far they are from their destination.

Padma noticed that the numbers on the kilometre stones were decreasing as she moved ahead. This helped her understand that she was getting closer to her destination.

👉 Example:
• Jaipur – 50 km
• Jaipur – 30 km
• Jaipur – 10 km
She could easily tell that Jaipur was approaching because the numbers were going down.

📍 The position of an object changes with respect to a reference point when the object moves from one place to another.

If the object does not move, its position remains the same.

👉 Example:
• If Padma walks from a tree towards a shop, her position keeps changing with time.
• But if she stands still beside the shop, her position does not change.

(i) The motion of a car moving on a straight road is an example of linear motion. — ✅ True

(ii) Any object which is changing its position with respect to a reference point with time is said to be in motion. — ✅ True

(iii) 1 km = 100 cm — ❌ False

(i) millimetre

(ii) centimetre

(iii) kilometre

(iv) handspan

💬 Explanation:
🖐️ The handspan is not a standard unit because it can differ from person to person.
Everyone’s hand size is different, so measurements using handspan are not accurate.
📏 Standard units like millimetre (mm), centimetre (cm), and kilometre (km) are fixed and universal, used everywhere for consistency.

👉 1 kilometre (km) = 1000 metres (m)

So,

1.5 km = 1.5 × 1000 m = 1500 metres

Steps:
1️⃣ Take a piece of thread and place it along the curved edge of the base.
2️⃣ Mark the starting and ending points on the thread.
3️⃣ Straighten the thread and measure its length with a scale.

🧵 Example:
If the curved thread length measures 25 cm, then 👉 The length of the curved part = 25 cm.

(i) In metres (m) = 1.4 m

(ii) In centimetres (cm) = 1.4 × 100 = 140 cm

(iii) In millimetres (mm) = 140 × 10 = 1400 mm

Step 1: Estimate
Let’s say the notebook side = 15 cm, and the diameter of one coin ≈ 2.5 cm.
👉 Estimated number of coins = 15 ÷ 2.5 = 6 coins.

Step 2: Verify
Place coins in a line along the notebook side. If the actual count = 6 coins, the estimate was correct!

Reason: Cloth and rubber are flexible and stretchable, so their length changes when pulled or stretched. They cannot give accurate measurements.

Best materials: She should use steel or plywood, because they are rigid and non-stretchable, ensuring correct and reliable measurements.

Materials: 20–30 cards (paper or thin cardboard), pen/marker.

How to make cards:
• Write a conversion question on the front and the correct answer on the back.
• Examples: Front: “1 km = ? m” → Back: “1000 m”; Front: “50 cm = ? mm” → Back: “500 mm”.

How to play:
1️⃣ Shuffle cards and keep them face down.
2️⃣ Each player picks a card and says the conversion aloud.
3️⃣ Correct answer → 1 point. Wrong → 0 points (optionally show the correct answer).
4️⃣ After all cards are used, the highest score wins.

Bonus round idea: Add “Challenge Cards” (e.g. “Convert 2.5 km to cm” or “Change 1200 mm to m”) with a 10-second time limit for extra points.