Why some objects sink while others float in water?

Float and Sink

Whether something is going to sink or float in water depends on the density of the object in water and the density of the water. Density is a measure of how much mass  is packed into a certain unit of volume. In short density is mass per unit of volume. The condition of sink and … Read more

Exploring Permutations and Combinations: A Simple Visual Guide for Students

Permutations and combinations are two important ideas in mathematics that help us count the number of possible ways to arrange or select objects. Combination Combination is used when order does not matter.For example, choosing 2 ice-cream flavors from 5.Chocolate + Vanilla is the same as Vanilla + Chocolate, so it is counted only once. Formula … Read more

Learn how hand water pump works with this DIY kit

Picture of a DIY Hand water pump

What is a hand water pump? A hand water pump is simple device that pulls water up from underground. It uses mechanical motion of hands to pull the water from the underground. It has a long handle that you move up and down.  When you do this, it uses air pressure and valves to pull … Read more

Why balloons move up in the air?

Balloons moving up in the air always fascinate us as children. But have you wonder why they move up in the air?   The underlying principal for balloons upward movement is the same as that of objects floating on water. The balloon moves in the upward direction due to difference in the densities of the … Read more

The Human Hearing Range Explorer

Humans can hear sounds in the frequency range of about 20 Hz (very low bass) to 20,000 Hz (very high pitch). Younger people—especially children—can usually hear higher frequencies than adults, and as we grow older, our ability to hear the highest pitches naturally decreases. The Human Hearing Range Explorer is a fun and interactive tool … Read more

Optical Lenses: Different Types, Uses, and Practical Applications

A minimalist flat-lay composition showing a variety of microscopes, telescopes, digital cameras, flash cameras, and eyeglasses neatly arranged on a soft pastel blue background.

Do you know what do cameras, eye glasses, telescopes and microscopes have in common? The object at the core of these devices is an optical lens. A lens is a transparent object and light is refracted when it passes through the lens. Lens is used in many optical instruments such as cameras, microscope, telescope, optical … Read more