The distance between a crest and a trough is $20 cm$ in ripples on the surface of water. When $20$ ripples are produced in one second, calculate the time period.

Important Questions on Sound

EASY

9th CBSE

IMPORTANT

LIVING SCIENCE PHYSICS 9>Chapter 6 - Sound>Exercises>Q E

The distance between a crest and a trough is

20 cm

in ripples on the surface of the water. When

20

ripples are produced in one second, calculate the wave velocity.

EASY

9th CBSE

IMPORTANT

LIVING SCIENCE PHYSICS 9>Chapter 6 - Sound>Exercises>Q E

The speed of sound is

330 m / s

. A person fires a gun. An echo is heard after

2 s

. Calculate the distance of the person from a cliff which echo takes place.

EASY

9th CBSE

IMPORTANT

LIVING SCIENCE PHYSICS 9>Chapter 6 - Sound>Exercises>Q F

Kriti was feeling bored. Her friend Khushi took a scale. She placed it on a table end and flicked it to produce a musical sound. Kriti was pleased at Khushi's gesture to entertain her. Why does the scale produce sound?

EASY

9th CBSE

IMPORTANT

LIVING SCIENCE PHYSICS 9>Chapter 6 - Sound>Exercises>Q F

Divisha and her friend Smita are on the moon. They wanted to share their experiences and feelings. Will Divisha be able to hear any sound produced by her friend Smita? Why?

EASY

9th CBSE

IMPORTANT

LIVING SCIENCE PHYSICS 9>Chapter 6 - Sound>Exercises>Q F

Lalitha was cleaning the middle ear using a matchstick. Her friend Suparns immediately stopped her from doing so. Why we should not clean our ears using a matchstick or any other pointed object?

EASY

9th CBSE

IMPORTANT

LIVING SCIENCE PHYSICS 9>Chapter 6 - Sound>Exercises>Q F

Rupesh was studying for his exams. His neighbour Berry was playing tabla. Rupesh was getting disturbed. He asked Berry to play tabla softly. Berry followed his advice. Why is soft sound produced when we strike a drum softly?