Shadows

Q. Why a flying aeroplane does not cast a shadow

Q.

Which kinds of objects do not form a shadow? Why?

Q.

The size of a shadow depends on

1. Distance between the object and the source of light.

2. Distance between the object and the shadow.

3. Different time intervals

4. The size of shadow cannot be changed.

Q. Write the differences between a shadow and an image. [5 MARKS]

Q.

Which of the following is not a required condition for shadow formation?

1. There must be an opaque body to obstruct the path of light.

2. There must be a source of light.

3. There must be an opaque screen to form the shadow.

4. There must be a transparent body to obstruct the path of light.

Q. The dark region which is formed when the path of light is blocked by an opaque object is called .

1. shadow
2. reflection
3. image
4. mirage

Q. Objects that form faint shadows are ________ in nature.

1. translucent
2. transparent
3. opaque
4. irregular

Q.

Question 17

A student covered a torch with red cellophane sheet to obtain red light. Using the red light she obtains a shadow of an opaque object. She repeats this activity with green and blue light. Will the colour of the light affect the shadow? Explain

Q. Dark patch formed when an opaque object is placed in the path of light is called:

1. Image
2. Object
3. Shadow
4. Screen

Q.

Shadow of an object is formed when the object

1. it allows the light to pass through it

2. it bounces back light

3. it absorbs light

4. both B and C

Q.

A region of partial darkness that surrounds the shadow is called the umbra.

1. True
2. False

Q. Why is a translucent screen used in a pinhole camera? Explain in detail.

Q. Write three differences between an image and a shadow.

Q. What will be the shape of the shadow formed on screen, if the light falls on a cone vertically as shown in the figure?

1. Square
2. Triangle
3. Circular
4. Conical

Q.

A shadow shows only the outline of the object.

1. True
2. False

Q.

True or False

A) A shadow is formed due to the rectilinear propagation of light

Q.

Which of the following objects is opaque?

1. Mirror

2. Water

3. Air

4. Lens

Q.

When the distance between the object and the source of light is decreases

Q. Write true or false :

If the shadows of earth falls on the moon, the eclipse is called the lunar eclipse.

Q.

The central dark region of a shadow is called the

1. penumbra.

2. umbra.

3. total shadow

4. core

Q. On which of the following factors the size of the shadow depends?

1. 
   Direction of light source
2. 
   Distance of light source from object
3. 
   Distance of screen from object
4. 
   Size of screen

Q.

Shadows are:

1. Always smaller than the opaque object.

2. Always bigger than the opaque object.

3. Remains the same size as the opaque object.

4. Can be smaller or bigger or same as compared to the opaque object.

Q.

What can be said about the shape of a shadow?

1. It is similar to the object

2. It is different from the object

3. It depends on the orientation of light source, distance between the source and the object

4. None of these

Q.

Can you suggest the shape of the shadows?

1. None of these

2. It is similar to the object

3. It depends on the orientation of light source, distance between the source and the object

4. It is different from the object

Q.

A region of darkness, which is formed when the path of light is blocked by an opaque body is called ___________.

1. Shadow

2. Luminosity

3. Darkness

4. Translucence

Q. A cylinder can cast a rectangular shadow.

1. True
2. False

Q. As compared to a metal sheet, an identical sized tracing paper will cast a ______ shadow.

1. darker
2. lighter
3. smaller
4. larger

Q.

Which of the following is false with respect to shadows and mirror images?

1. Both can form from the light source only

2. Both form different colors of images

3. Both have different sizes which is variable in nature.

4. None of these

Q.

People cast a shadow on the ground as they walk because they block:

1. View

2. Way

3. Light

4. Scene

Q.

What can you say about the edges of a shadow?

1. They are sharp and distinct

2. They are blurry but distinct

3. They are different from the object

4. None of these