Buoyancy

Why does a piece of iron sinks but a ship made of the same iron floats?
To understand this you must know what Archimedes’ Principle is.
Archimedes’ Principle states that a body immersed in a liquid, wholly or partly, loses its weight. The loss of weight is equal to the weight of the liquid displaced by the body. Here the ship floats because the amount of water that they displace, weighs more than the ship itself. It's called the law of Buoyancy.If the buoyant force is greater than the gravitational force, the object will float, but if the opposite is true, the object will sink.

Walking and Running

What is the difference in leg movement while walking and running?
While running your toe hits the ground first whereas while walking heel hits first.

Pulling or Pushing

Which one is easier ‘Pulling or Pushing’?
When you apply force on an object to pull it, the vertical component of the force act in the opposite direction of weight and this decreases the apparent weight of the body. When you push, the vertical component acts in the same direction as that of the weight and more work is to be done to displace the body. Therefore pulling is easier than pushing.

Climb upstairs

Why it is harder to walk up the stairs?
As you climb up the stairs you are carrying your own body
weight against gravity.

Maida and Atta

We Keralites are familiar with Maida, the main ingredient of porotta. What is the difference between Maida and Atta?
Both Maida and Atta flour are made from wheat. The only difference is Atta is whole wheat flour and Maida is refined and finely-milled product of wheat. Maida is extracted from the inner white portion of the wheat after the outer brownish layer is removed.