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   CBSE CLASS IX, SOUND, SCIENCE (PHYSICS) NOTES- (PART II)                                 SOUND According to the CBSE Syllabus 2025-26 CBSE Class 9 Science Chapter 12 Sound Notes Remaining Topics of this Chapter 10. Velocity 11. Speed of sound in various medium 12. Sonic Boom 13. Reflection of Sound 14. Echo 15. Reverberation 16. Range of Hearing 17. Hearing Aid 18. Application of Ultrasound 19. SONAR 20. Structure of the Human Ear a. Working of the Human Ear QUALITY OF SOUND The richness or timber of sound is called quality. Sounds with the same pitch and loudness can be distinguished based on their quality. Music is pleasant to the ears, while noise is not. However, they both can have the same loudness and pitch.   SPEED OF SOUND IN VARIOUS MEDIUMS Sound travels through different media at different speeds. The speed of sound depends on the properties of the medium, pressure, density,...

  CBSE CLASS IX, SOUND, SCIENCE (PHYSICS) NOTES- (PART I)                                 SOUND According to the CBSE Syllabus 2025-26 Topics in the Chapter 1. Introduction 2. Production of Sound 3. Propagation of Sound 4. Sound waves are Longitudinal waves 5. Characteristics of a Sound Wave 6. Wavelength 7. Frequency 8. Time Period 9. Amplitude a. Pitch b. Loudness c. Quality or Timbre 10. Velocity 11. Speed of sound in various medium 12. Sonic Boom 13. Reflection of Sound 14. Echo 15. Reverberation 16. Range of Hearing 17. Hearing Aid 18. Application of Ultrasound 19. SONAR 20. Structure of Human Ear a. Working of Human Ear   INTRODUCTION The sensation felt by our ears is called sound. Sound is a form of energy that makes us hear. The law of conservation of energy is also applicable to sound. Sound travels in the form of a wave. PRODUCTION OF SOUND I. Sound is produced...

  CBSE CLASS IX, WORK AND ENERGY, SCIENCE (PHYSICS) NOTES- (PART II)                         WORK AND ENERGY According to the CBSE Syllabus 2025-26 CBSE Class 9 Science Chapter 11 Work and Energy Notes In Class 9 Science Chapter 11  Work and Energy . Remaining Topics in the Chapter 5. Forms of Energy                                                     a. Mechanical Energy.                                                 b. Kinetic Energy. 6. Potential Energy. 7. Transformation Energy. 8. Law of conservation of Energy. 9. Free Fall of a Body (Energy Conservation). 10. Power. a. Un...

  CBSE CLASS IX, WORK AND ENERGY, SCIENCE (PHYSICS) NOTES- (PART I)                         WORK AND ENERGY According to the CBSE Syllabus 2025-26 CBSE Class 9 Science Chapter 11 Work and Energy Notes In Class 9 Science Chapter 11  Work and Energy . Topics in the Chapter 1. Introduction 2. Work a. Conditions for work to be done.        b. Conditions when work is not done.      c. Unit of Work. 3. Negative, positive, and Zero Work 4. Energy 5. Forms of Energy                         a. Mechanical Energy.           b. Kinetic Energy. 6. Potential Energy. 7. Transformation Energy. 8. Law of conservation of Energy. 9. Free Fall of a Body (Energy Conservation). 10. Power a. Unit of Power 11. Commercial unit of Power a. Solved Numerical INTRODUCTION TO WORK AND ENERGY Class 9 Chapter ...