Why is an electronic watch called quartz?...

Is it true that ice from fresh sea water is fresh?...

Why does water freeze? Description, photo and video...

How and why do airplanes fly? Description, photo and video...

X-ray sources...

Why does ultraviolet kill microbes? Reasons, photos and videos...

Why is glass and ice transparent? Description, photo and video...

What is the blackest material in the world?...

Why is the boomerang coming back? Explanation, drawings, photos and videos...

Why do drops remain on the glass? Photo and video...

Why is hair electrified? Explanation, photos and videos...

How and why are icicles formed? Description, photo and video...

How do rockets fly? Description, photo and video...

Why is it shocking? Explanation, photos and videos...

Why is neon glowing? Gas glow - description, photos and video...

How to make a time travel? Photo and video...

How is x-ray done? Description, photo and video...

What do substances consist of?...

Why is soap washed off more easily with warm water?...

What are molecules made of?...