STD 3 EVS Chapter 11: Curiosity in Daily Life – Complete Questions and Answers (Pages 118–128)
STD 3 EVS | Chapter 11: Curiosity in Daily Life | Complete Answers (Pages 118–128)
Introduction
In this chapter, students learn about different materials, natural and man-made objects, properties of substances, water-soluble and insoluble materials, states of matter, simple machines, electrical appliances, sound, air pressure, and interesting classroom activities. Below are the complete answers in simple language.
Page 118
Observe the Objects and Complete the Table
| Object | Substance Used | Other Objects Made from the Same Substance |
| Chair | Wood | Door, Wooden Toys, Rolling Board (Polpat), Table |
| Tawa | Iron | Kadai, Pot, Pan |
| Bangles | Glass / Plastic | Glass, Bottle, Comb |
| Handkerchief | Cloth | Shirt, Saree, Towel |
| Bucket | Plastic | Mug, Bottle, Tub |
Page 119
Natural and Man-made Objects
Natural Objects
- Tree
- Stone
- Soil
- Flower
- Cotton
Man-made Objects
- Brick
- Lock
- Glass
- Sweater
- Eraser
- Scale
Properties of Objects
Hard
- Brick
- Lock
- Wooden Piece
Soft
- Cotton
- Sweater
Rough
- Brick
- Tree Trunk
- Coal
Smooth
- Glass
- Scale
- Lock
Brittle
- Glass
- Chalk
- Scale
Activity
Required Materials
- Glass tumbler
- Spoon
- Water
- Salt
- Sugar
- Sand
- Milk
- Oil
Procedure
- Take water in a glass.
- Add salt and stir.
- Observe the result.
- Repeat with sugar, sand, milk and oil.
- Record your observations.
Page 120
Water-soluble and Water-insoluble Substances
| Water-soluble | Water-insoluble |
| Salt | Sand |
| Sugar | Oil |
| Milk |
Observation
What happened to the ice cubes?
Answer:
The ice cubes melted into water. After some time, the water evaporated.
Page 121
States of Matter
Solid
- Block
- Tea Powder
- Rice
- Stone
Liquid
- Sherbet
- Ghee
- Milk
- Petrol
- Honey
Gas
- Fog
- Smoke
- Air
- Steam
Page 122
Activity
Opening a Tin Can
Observation
The lid could not be opened easily by hand.
Using a spoon made it easier to open.
The spoon acts as a Simple Machine.
Simple Machines and Their Uses
| Simple Machine | Use |
| Needle | Stitching cloth |
| Tongs | Picking hot objects |
| Scissors | Cutting paper and cloth |
| Ramp | Moving heavy objects |
| Pulley | Drawing water from a well |
| Screwdriver | Tightening and loosening screws |
Page 124
Electrical Appliances
- Electric Iron
- Television
- Mixer
- Street Light
Earlier and Modern Appliances
| Modern Appliance | Earlier Appliance | Purpose |
| Mixer | Mortar and Pestle, Grinding Stone | Grinding food |
| Electric Iron | Charcoal Iron | Ironing clothes |
| Television | Radio, Storytelling | Entertainment |
| Street Light | Oil Lamp, Lantern | Lighting |
Page 125
Activity
Sound and Vibrations
Observation
When the plate was struck, sound was produced.
When touched with the hand, vibrations stopped and the sound also stopped.
Create Musical Instruments
Example Sounds
- Ting Ting Tak
- Dab Dab Dhoom Dhoom
- Tak Tak Ting
Page 126
Air Pressure Activity
Observation
Blowing air moved the bottle cap without touching it.
Identify the Machines
| Machine | Air Pressure ✱ | Electricity ☑ |
| Pressure Cooker | ☑ | |
| Ceiling Fan | ☑ | |
| BP Machine | ✱ |
Page 127
Identify the Machines
| Machine | Air Pressure ✱ | Electricity ☑ |
| Computer | ☑ | |
| Hot Air Balloon | ✱ | |
| Pump | ✱ |
Let’s Revise
A. Odd One Out
- TV, Fridge, Mixer, Mortar and Pestle
Answer: Mortar and Pestle
- Doorbell, Knife, Spoon, Scissors
Answer: Doorbell
- Wood, Glass, Cotton, Iron
Answer: Glass
B. Guess Who Am I?
1.
I am hard and rough. I am used for making furniture.
Answer: Wood
Page 128
Guess Who Am I?
2.
I am shiny and brittle.
Answer: Glass
3.
I am soft and used for making clothes.
Answer: Cotton
4.
I am hard and used for making utensils.
Answer: Iron
C. Answer
How will you stop the sound of a plate quickly?
Answer:
Touch the plate to stop its vibrations.
D. Brittle Substances
- Glass
- Chalk
- Scale
E. Water-soluble and Water-insoluble Substances
Dissolve in Water
- Salt
- Sugar
- Milk
Do Not Dissolve in Water
- Oil
- Sand
F. Properties of Substances
Answer:
- Hard
- Smooth
Activity
- Create a toy that works on air pressure.
- Draw an electrical appliance.
- Colour it.
- Write the precautions to use it safely.
Key Takeaways
- Objects are made from different materials.
- Materials have different properties.
- Some substances dissolve in water while others do not.
- Matter exists in three states: solid, liquid and gas.
- Simple machines make our work easier.
- Electrical appliances help us in daily life.
- Sound is produced because of vibrations.
- Air pressure can move objects.