What is the primary requirement for seeing objects around us?

Light is the primary requirement for seeing objects, as it bounces off objects and reaches our eyes.

Luminous objects are defined as those that ___ .

Emit light on their own.

True or False: Non-luminous objects can be seen because they emit light.

False. Non-luminous objects do not emit light; they are seen when light shines on them.

Fill in the blank: Examples of luminous objects include the ___ and a ___ .

Sun; lit candle

What allows non-luminous objects to be visible?

Non-luminous objects are visible when light from luminous objects shines on them and reflects into our eyes.

Multiple Choice: Which of the following is NOT a luminous object? A) A candle B) A chair C) The sun D) A glowing bulb

B) A chair

What is the difference between luminous and non-luminous objects?

Luminous objects emit light on their own, while non-luminous objects do not emit light and can only be seen when illuminated by light from luminous sources.

What type of medium allows all light to pass through it without obstruction?

A transparent medium allows all light to pass through it.

Fill in the blank: Objects that allow only some light to pass through are called ___ media.

Translucent

Riddle: I am something you can see through, but I am not air. I can be a window or a glass. What am I?

A transparent object.

What distinguishes opaque objects from translucent objects?

Opaque objects do not allow any light to pass through, while translucent objects allow some light to pass through but not enough for a clear view.

Fill in the blank: Examples of translucent media include ___ and ___.

Smoked glass and butter paper

What is the main reason shadows are formed?

Shadows are formed because a solid object blocks the light from a source, preventing it from reaching a surface.

Fill in the blank: To see a shadow, you need a ___ and a ___ object.

Source of light; solid

True or False: Shadows can appear on any surface regardless of its material.

False: Shadows can only appear on surfaces like the ground, a wall, or a piece of paper.

How does the position of an object relative to a light source affect its shadow?

The position of an object relative to a light source affects the size and shape of the shadow; moving an object closer or farther from the light changes how the shadow appears.

Multiple Choice: What do you need to create a shadow? A) Only light B) Only a solid object C) Light and a solid object D) A screen

C) Light and a solid object

What is the primary mechanism through which a pinhole camera captures images?

A pinhole camera captures images by allowing light to enter through a small hole, creating an inverted image on the surface inside.

Fill in the blank: A pinhole camera does not use a ___, but rather relies on a small hole to let light in.

Lens

True or False: The image produced by a pinhole camera is upright.

False. The image produced is inverted.