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Correct option is  B) lenses

Correct option is  B) small

Correct option is  A) 2

1. If we make two pin-holes in the camera I predict that images are not clear. 

2. But it is a wonder that it forms two images, both are clear.

1. Why shadows are always black? 

2. Why sometimes shadows are small and large? 

3. Why our shadows always follows us? 

4. Can we guess the time when see the shadow?

Opaque: 

An object which does not allow light to pass through it and you are not able to see the objects behind your opaque material. 

Transparent: 

An object that allows light to pass through it and you can see the objects behind your transparent material.

1. I find that glass slab does not form a shadow. 

2. I observed the shadow of my hand. 

3. It means glass slab is a transparent object and hand is opaque object. 

4. My conclusion is that only opaque objects form clear shadow. 

5. And transparent objects does not form shadows.

1. Between electric bulb and tube light electric bulb forms clear and sharp image. 

2. Electric bulb is round in shape. 

3. It takes more voltage and forms intensity light 

4. That’s why electric bulb forms sharp and clear shadows. 

5. But at the tube light shadow it is not sharp. 

6. Here light source is lengthy. 

7. And light fell on objects from different side. 

8. So the shadow does not sharp.

1. In the colour light opaque objects forms shadows. 

2. But they does not have any colour. 

3. because shadow is the place where the light is prevented. 

4. It does not effected by colour light.

Rectangular, square, line, rhombus, triangle.

Yes, both shadows are round in shape.

i) No the object can’t visible to me.

ii) Light can’t reach the eyes. So it is not visible.

iii) Plank prevent the light. So it can’t reach the eyes.

iv) Its light that causes sight sense.

v) A substance which gives light is known as a light source.

vi) Objects give us light are Sun, a glowing bulb, lighted candle etc.

vii) Sun, stars, torch, candle, bulb, flame, glowing worm.

viii) I saw the shadow at day time.

ix) No, generally shadows does not form at night time. We may form shadows by using light at night time.

x) Its not possible to form shadows without light.

xi) We need light to get the shadow of any object.

i) No, he not able to guess the colour.

ii) No, its not possible to guess the colour of the object by observing its shadow. Because any colour of object forms only dark shadows. A shadow is an area/where light is absent. Hence, the shadow is colourless irrespective of the colour of the object.

We need light to see objects.

When we gradually rotate the object towards the light source, the square shadow change into triangle.

When I just bend the rectangular cardboard in front of light source, it forms square shaped shadow.

Substance which gives light is known as a source of light.

No. I am not able to make a circular shadow.

• Due to the regular reflection of light, we look at our image in the plane mirror. 
• We can turn the sunlight towards dark places by the regular reflection of light with the help of a shiny surface. 
• The wing and rear-view mirrors of a car are made of a convex and a plane mirror respectively. 
• A microscope uses a mirror to reflect light to the specimen under the microscope.

1. The substances like paper, plank, wood, iron, etc. don’t allow light to pass through them. These objects form shadows. These are called opaque substances. 

2. The substances like glass and air allow light to pass through them and hence we don’t get their shadows. Such substances are called transparent substances. 

3. The substances such as polyethylene cover and oily paper partially allow the light to pass through them. Their shadows are unclear. These substances.

(i)  Object

(ii)  sun

(iii) Translucent

(iv) transparent

(v) Puppet show

(vi) Screen

Correct option is  D) mirror

Correct option is C) glass

We need a source of light and an opaque object and a screen to get a shadow.

Yes, we can’t identify the presence of completely transparent objects even in Light. Because it allows light to pass through it. So we can’t find it.

A. shadow is a dark area where light from a light source is blocked by an opaque object. 

B. The object may have different shapes in different angles. 

C. So, the shadow shape is changed.

The reflected light behind objects of us can’t reach our eyes. So we can’t see objects which are behind us.

1. straight line.

2. light source.

3. reflection.

4. Black.

In ancient days, by observing the shapes of shadows people came to an understanding that light travels in a straight line.

Correct option is  D) glass

Yes, we can show the difference between shadows and images through a drawing.

1. In images, we can use color and draw the whole picture. 

2. Whereas in shadows we draw only outline and fill with black.

Light gets reflected when it falls on any object.

Shadows are formed when opaque objects obstruct the path of light.

The correct answer is C) Glass.

To get a shadow we need 

1. light source 

2. opaque body 

3. screen.

In addition to light and object we also need a screen to obtain the shadow of an opaque object.

Light travels in a straight line.

The correct answer is C) Opaque.

1. Its simple technique to appear to my friend in mirror. 

2. In mirror image formed by reflection. 

3. In reflection light bounce in same angle. 

4. That’s why I am visible to my friend when he is visible to me. 

5. So, I adjust my place until my friend appear to me. 

6. When my friend visible to me, I am also visible to my friend.

I found that duster have different shadows in different positions by rotating it. Some times the shadow seems as duster and sometimes not.

The colour of objects cannot be determined by looking at their shadows.

The correct answer is D) All the above.

1. Mostly we guess the object by observing its shadow. 

2. But it is not always possible. 

3. Sometimes the shadow may differ from the shape of the object. 

4. Because of light source position and shape of the object.

The pen shadow is different when you hold the pen horizontally and then vertically. When you hold the pen vertically the shadow seems as object. When you turn the pen horizontally the shadow become round in shape.

No. I can’t agree with this statement. I understand that only light and an opaque object are not enough to form the shadow of an object. In addition to these, we need a screen.

i) The image on the white drawing sheet is inverted.

ii) I notice that the image formed through the magnifying lens is clearer than that formed with a pinhole camera.

iii) 

Similarity: 

Shadow and image are related to light. Without light both are not visible.

Difference: 

The key difference between image and shadow is that the image is the reflection of the light rays by an object, whereas the shadow is a dark shape projected onto a surface when an opaque object obstruct the light rays. The term image generally refers to an optical representation of a real object. A shadow is black in color while an image is colorful, and represents the real colors of the object it represents.

Because of the straight line path followed by light rays, we can get different shaped shadows for a single object by changing its position.

In the dark light is not sufficient to see the objects.