Which of the following is a natural source of light? A) Bulb B) Candle C) Sun D) Torch

C) Sun

What type of objects are called luminous objects?

Objects that give their own light.

True or False: Non-luminous objects can produce light on their own.

False. Non-luminous objects do not give their own light and can only be seen when illuminated by a luminous object.

Riddle: I am a material that allows light to pass through completely, making everything clear. What am I?

Transparent material

Fill in the blank: The phenomenon when light is spread in various directions after striking a medium is called ______.

Scattering of light

What is the speed of light in meters per second?

3 x 10⁸ meters per second

Which type of beam occurs when light rays come together at one point?

Convergent beam

Fill in the blank: An opaque object does not let light pass through it and always creates a ______.

Shadow

True or False: A shadow can be seen clearly only when there is a screen behind the object casting it.

True.

What happens during a total solar eclipse?

The moon fully covers the sun, blocking all sunlight from reaching parts of Earth.

Which type of eclipse occurs when the Earth comes between the sun and the moon?

Lunar eclipse

Riddle: I block the sun's light and cast a dark spot, but I'm not a cloud. What am I?

An opaque object

Fill in the blank: The lighter part of a shadow where some light reaches is called ______.

Penumbra

What is the role of bio-luminescence in living organisms?

To see better in the dark, attract prey, communicate, hide, or escape from predators.

True or False: A pinhole camera can take pictures of moving objects.

False. A pinhole camera can only take pictures of still objects.

What type of material lets light pass through but not completely, making it look foggy?

Translucent material

Fill in the blank: The image formed by a pinhole camera is always ______.

Inverted

What is the definition of an eclipse?

An event where one object blocks the light of another.

Which type of eclipse is characterized by the moon appearing smaller than the sun, creating a ring of light?

Annular solar eclipse

Riddle: I am formed when light is blocked, casting a dark shape on the ground. What am I?

A shadow

Fill in the blank: Light travels in a straight line due to ______.

Rectilinear propagation of light

What determines the clearness and length of a shadow?

The position of the light source.

True or False: Transparent objects block all light and create a shadow.

False. Transparent objects do not create a shadow as they allow all light to pass through.

What do we call the darkest part of a shadow?

Umbra

Fill in the blank: The moon shines by ______ the sun's light.

Reflecting

What can be used to safely observe a solar eclipse?

Pinhole camera

What is the main reason we cannot see eclipses every month?

The tilt of the moon's orbit at an angle of 5 degrees.

Riddle: I am not a light source but can show you a dim image of what's outside when pointed at it. What am I?

Pinhole camera