Explain why, if you hold a thin strip of paper just below your lips and blow air over its surface from your mouth, the strip of paper lifts up.

What conclusion do you get from the observation that if you hold a thin strips of paper just below your lips and blow air over its surface from your mouth, the strip of paper lifts up ?

Explain why we cannot remove a filter paper from a funnel by blowing air into its narrow end.

(a) When we put our ear to a railway line, we can hear the sound of an approaching train even when the train is far off but its sound cannot be heared through the air. Why? (b) How could you convince a small child that when you speak, it is not necessary for air to travel from your mouth to the ear of a listener?

(a) Gallinule (an aquatic bird with exceptionally long toes that are spread out over a large area) can actually walk across lily pads without sinking. Explain. (b) One day while ewimming below the surface of the ocean, you let out a small bubble of air from your mouth. What happens to the bubble as it rises towards the surface?