skill bulider

skill bulider

Light and Sound

Recap and apply the concept to answer the questions.     

LIGHT

Sources of light

All sources of light can be classified as Natural sources and Artificial sources of Light.

Natural light

Eg: Sun, Firefly, stars

Artificial light

Eg: Bulb, lamp, candle

Objects can be classified as Luminous and Non-Luminous Objects

Transparent , Translucent and Opaque 

Objects are classified as transparent, opaque and translucent based on how much light they allow to pass through them.

TRANSPARENT OBJECTS

Eg:- clear glass, clean air, clean water

TRANSLUCENT OBJECTS

Eg:- tissue paper, butter paper, frosted glass

OPAQUE OBJECTS

Eg:- wood, metal, wall 

SHADOW

Shadows are formed when objects block the path of light.

Shadows are always formed in the opposite direction of the light.

Length of the shadow depends on the position of the source of light. 

SOUND

The sounds that we make may be pleasant or unpleasant.

Sound is made when an object vibrates

Multiple Choice

1.The object shown here, does not cast a clear shadow. It is most likely made of __________________ material.

• A. metal

• B. Wood

• C. clear plastic sheet

• D. rubber

Multiple Choice

Strings of a guitar are pulled to create vibrations. What do vibrations produce?

• Colour

• Sound

• Light

• Force

Multiple Select

Look at the picture. Some birds have feet that help to hold on to branches tightly and sit on them. Identify these birds (Select all correct answers)

• Pigeon

• Penguin

• Parrot

• a.Pelican

Multiple Select

Study the given Venn diagram and select the correct options regarding it.

• X is parrot

• Y is woodpecker

• W is duck

• Z is heron