Chapter 8: Sound and Noise
Question Answers

A. Tick the correct option

1. Which animal makes a chirping sound? Bird

2. Sound that makes us relaxed is pleasant sound.

3. Ambulance alerts people about danger with loud warning sounds.

4. Noise from machines causes noise pollution.

5. Noise pollution can cause headache and earache.

B. Fill in the blanks

1. We cannot see sound but hear it.

2. Animals and birds make many different types of sound.

3. Warning sounds are used to alert people.

4. Soft and pleasant sounds make us feel good.

5. A loud and unpleasant sound is called noise.

C. True / False

1. All objects produce the same kind of sound. F

2. Unpleasant sound is good for health. F

3. Musical instruments produce pleasant sound. T

4. Constant exposure of noise may damage our eardrums. T

5. Bursting fire crackers should be encouraged. F

D. Give two examples of each

1. Pleasant sounds – Gentle chirping of birds, Sound of musical instruments

2. Sounds made by animals – Barking of dogs, Meowing of cats

3. Vehicles that use siren – Ambulance, Fire engine

4. Unpleasant sounds – Loud sound of aircraft, Noise from generators

5. Sources of noise – Machines in factories, Bursting of firecrackers

E. Differentiate between

1. Sound vs Noise
Sound: Produced when an object vibrates and we hear it.
Noise: Loud and unpleasant sound that causes disturbance.

2. Pleasant vs Unpleasant sounds
Pleasant: Enjoyable and relaxing. Eg: Music, birds chirping
Unpleasant: Irritating and stressful. Eg: Honking, loudspeakers

F. Answer the following questions

1. Four sounds made by living beings
Talking, laughing, barking of dogs, chirping of birds.

2. Warning sound
Warning sounds are loud sounds that are used to alert people about any kind of danger or emergency. Eg: Sirens of ambulance, fire engine, and fire alarm.

3. Why do fire engines have a siren?
To warn people to give way so fire engines can reach quickly to control fire and rescue people.

4. What do you mean by “noise pollution”? Write any three ill effects of noise pollution.
Excessive amount of noise that affects the health of living organisms is called noise pollution.
Effects: Headaches and earaches, damage to eardrums, disturbed sleep.

5. Ways to reduce noise pollution
Ban loudspeakers, avoid honking, keep vehicles in good condition, plant trees, listen to music/TV at low volume.

Note: Avoid noise pollution. Keep volume low and speak softly 🔊