Sound
13 solved questions from Class 9 Science, each with the full working. Tap any question to see the step-by-step solution.
- 1 What is the fundamental scientific concept introduced in the chapter 'Sound'? medium MCQ Key Concept & Definition
- 2 Which of the following is an important application or observation related to 'Sound'? easy MCQ Practical Application
- 3 What primary question does the chapter 'Sound' aim to answer? medium MCQ Core Scientific Inquiry
- 4 Why is the study of 'Sound' essential for students in class-9? hard MCQ Importance & Significance
- 5 Which key practice is recommended while studying topics in 'Sound'? medium MCQ Scientific Method
- 6 What is the primary topic or theoretical principle explored in 'Sound' (Class 9 SCIENCE)? medium MCQ Chapter Core Principle
- 7 Which key mechanism or analytical rule is highlighted in 'Sound'? medium MCQ Key Analytical Mechanism
- 8 A tuning fork vibrates at 512 Hz. If the speed of sound in air at room temperature is 340 m/s, what is the wavelength of the sound produced? easy 1 mark wavelength of sound
- 9 A train emits a sound at 600 Hz and moves at 30 m/s towards a stationary observer. If the speed of sound in air is 330 m/s, what observed frequency will the observer hear as the train approaches and then recedes? hard 4 marks Doppler effect for sound
- 10 A wooden bar of length 2 m is fixed at one end and free at the other end. Its fundamental frequency of vibration is 200 Hz. Calculate the speed of vibration waves in the bar. medium 3 marks wave speed from resonator frequency
- 11 A speaker emits sound of frequency 880,Hz. The speed of sound in air is 343,m/s. What is the wavelength of the sound produced? easy 1 mark Wavelength of sound
- 12 In an open–open pipe of length 0.8,m, the fundamental (first harmonic) is produced. If the speed of sound is 340,m/s, what is the frequency of this first harmonic? medium 2 marks Standing waves in open–open tube
- 13 Explain how the speed of sound in air depends on temperature. A source emits sound of frequency 300,Hz. If the ambient temperature changes from 20°C to 30°C, calculate the change in frequency observed by a stationary observer, assuming the source frequency remains unchanged. Use v = 331 + 0.6T where T is in degrees Celsius. hard 3 marks Temperature effect on speed of sound, frequency invariance