Question

when we blow a glass bottle and a plastic bottle we hear a shrill sound from a plastic bottle why​

Answer 1

Explanation:

When you blow across the top of an open bottle the air inside it vibrates, producing sound waves we can hear. When we blow across an empty bottle there is more space for the air to vibrate in, so the air vibrates more slowly. We hear a lower pitch.

Answer 2

A plastic bottle will create a shriller sound than a plastic bottle.

Explanation:

• A plastic bottle will create a shriller sound than a plastic bottle.
• We hear a shrill sound from a plastic bottle, the particles of plastic are very closely packed in plastic.  
• Plastic is a dense material and the air column inside it produces a shrill sound.
• When it comes in contact with air the particle vibrates a little and produces a shrill sound.