76

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Unit 1.P.2: Sensing Sound

• Sensing sound • Experiencing sounds

Science skills:

• Predicting • Observing • Classifying

By the end of this unit you should know:

• We use our senses to detect sound.

• We hear things with our ears.

• Animals have sharper hearing than humans.

• Having two ears helps tell us where a sound is coming from.

• There are sounds that are either too high or too low for us to hear.

77

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Ears – Our sensory receptors

We hear with our ears. Our ears also help us to detect where a sound is coming from. Children have more sensitive ears than adults. They can recognize a wide variety of sounds.

Animals hear more sounds than humans.

Dolphins have the best sense of hearing among animals. They are able to hear 14 times better than humans.

1.9.1, 1.9.2, 1.9.5

78

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Activity (1):

A. Say whether the following statements are true or false.

1. We hear with our ears. ( )

2. Our ears can hear the faintest sounds.( )

3. Animals hearing is sharper than humans.( )

4. Dolphins can hear 14 times better than us.( )

B. Read the passage on page, and fill in the blanks.

1. Our __________ help us to detect sounds.

2. Ears warn animals from their ____________.

3. Dolphins have the best sense of ___________.

4. Children have more sensitive ears than

___________.

79

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Activity (2): Experiment

Go for a listening walk around your school compound and try listening to different sounds:

Hear everything

Hear some things

Hear nothing

Both ears

One ear covered

Both ears covered

80

Physical processes

Grade1, Unit 1P.2. Sensing sounds

How ears help animals?

Most of animals have strong sense of hearing. Ears help them to find prey and to help themselves in keeping safe from their enemies.

Rabbits have large ears to help them hear their predators coming even before they get there.

Bats use their sense of hearing to help them find food. They can use their sense of hearing to detect trees and buildings.

The elephants can also use their ears to

81

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Activity (3): Circle the correct animal

1. Ears help them to find food.

2. They have large ears to sense danger.

3. Their ears are hard to see.

82

Physical processes

Grade1, Unit 1P.2. Sensing sounds

How to protect our ears?

Experiencing Sound

Our ears, are one of the most important sense organs. If our ears are working well, we hear sounds all the time.

Following are some healthy ways by which we can keep our hearing sound and clear.

• Clean your ears with extra care. • Do not put anything into your ear. • Do not use cotton buds, bobby pins or sharp

pointed objects to clean your ears. These objects may harm your ear.

• Wear hearing protection if there is a loud noise around you. Use your hands If you have to!

• When you are using a CD/MP3 player the volume should be comfortable, and NOT loud.

• Always wear a helmet when you bike, ski, roller blade or in any other activity that you might hurt your head and ears.

• If you ears hurt after swimming, because of water getting in, use ear blocks!

83

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Some common sources of sound

Baby crying Musical instrument

Emergency services Transport

Thunder Loud speaker

84

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Experiencing sound:

Soft and loud Sounds

There are a lot of sounds around us. Some sounds are loud and some are soft.

Soft sounds cannot be heard from a distance. A whisper is a soft sound.

Loud sounds also warn us of danger. We can hear the siren on a fire truck from a distance because it is loud. It also

warns people to move out of the way.

1.9.1, 1.9.6

85

Physical processes

Grade1, Unit 1P.2. Sensing sounds

LOUD and SOFT Sounds

Activity (1): Circle the pictures that show loud sounds.

86

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Activity (2):

Sort the sounds: quiet/ loud

87

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Activity (3):

Match the word to the picture

Sing

Clap

Whisper

Shout

Laugh

88

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Activity (4):

Here are some musical instruments. How are they played?

pluck shake hit blow

_________________

_________________

_________________

_________________

89

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Key Question

Name five ways in which you can look after your ears and hearing.

• _____________________________

• _____________________________

• _____________________________

• _____________________________

• _____________________________

Name two animals which use their sense of hearing to find food.

1. ____________

2. ____________

90

Physical processes

Grade1, Unit 1P.2. Sensing sounds

Key Words: sound soft low noisy high musical quiet ear loud drum shakers

Key idea • We use our ears to hear. • Sounds can be soft or loud. • There are a lot of sound sources around us.

Project Make your own musical instrument.

• Cut the neck off a balloon and throw it

away. • Stretch the rest of the balloon over one

end of a cardboard tube. • Talk down the open end of the tube and

gently place a finger on the balloon to feel what is happening.