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The graphical representation of two sound waves A and B propagating at the same speed of 345 m s⁻¹ is shown in Fig. 10.33. What is the wavelength of each of them? Also, calculate their frequencies.
(i) Wave A: One complete oscillation covers 2.5 cm along the distance axis, so its wavelength is 0.025 m. Dividing the wave speed of 345 m s⁻¹ by 0.025 m gives a frequency of 13,800 Hz. (ii) Wave B: One complete cycle spans 5.0 cm, giving a wavelength of 0.05 m. Dividing 345 m s⁻¹ by 0.05 m gives aRead more
(i) Wave A: One complete oscillation covers 2.5 cm along the distance axis, so its wavelength is 0.025 m. Dividing the wave speed of 345 m s⁻¹ by 0.025 m gives a frequency of 13,800 Hz. (ii) Wave B: One complete cycle spans 5.0 cm, giving a wavelength of 0.05 m. Dividing 345 m s⁻¹ by 0.05 m gives a frequency of 6900 Hz.
For more NCERT Solutions of Class 9 Science Exploration Chapter 10 Sound Waves Characteristics and Applications Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-10/
See lessTwo identical sound sources are placed at A and B—one in air and one submerged in water (Fig. 10.34). Both produce sounds at the same time, which travel horizontally to the vertical side of the cliff and come back. If the time taken by the sound to return to A is 4.5 times than that of B, what is the ratio between the speeds of sound in air and water?
Both sound waves cover the identical distance to the vertical cliff and back. Because wave speed equals distance divided by time, speed is inversely proportional to the transit time. Since the time taken in air is 4.5 times that in water, the ratio of the speed of sound in air to that in water is 1Read more
Both sound waves cover the identical distance to the vertical cliff and back. Because wave speed equals distance divided by time, speed is inversely proportional to the transit time. Since the time taken in air is 4.5 times that in water, the ratio of the speed of sound in air to that in water is 1 to 4.5, which simplifies to 2:9 (or roughly 0.22).
For more NCERT Solutions of Class 9 Science Exploration Chapter 10 Sound Waves Characteristics and Applications Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-10/
See lessA flower’s anthers are removed before it matures. Later, pollen from another plant of the same species is dusted onto its stigma and seeds are produced. Which process has been ensured here? (i) Self-pollination (ii) Cross-pollination (iii) Fertilisation (iv) Tissue culture
The correct option is (ii) Cross-pollination. Cross-pollination involves the transfer of pollen grains from the anther of one plant to the receptive stigma of a different plant of the same species. Emasculation or removing the immature anthers, eliminates any possibility of self-fertilization, ensurRead more
The correct option is (ii) Cross-pollination. Cross-pollination involves the transfer of pollen grains from the anther of one plant to the receptive stigma of a different plant of the same species. Emasculation or removing the immature anthers, eliminates any possibility of self-fertilization, ensuring that subsequent dusting of external pollen artificially accomplishes cross-pollination.
For more NCERT Solutions of Class 9 Science Exploration Chapter 11 Reproduction How Life Continues Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-11/
See lessArrange the following stages of sexual reproduction in plants in the correct order: (i) Pollen germination on stigma (ii) Fertilisation (iii) Pollination (iv) Formation of zygote
(i) First, pollination occurs when pollen grains transfer from the anther to the flower stigma. (ii) Second, pollen germination takes place on the stigma, developing a pollen tube down the style. (iii) Third, fertilisation happens when the male gamete reaches the ovule and fuses with the egg cell. (Read more
(i) First, pollination occurs when pollen grains transfer from the anther to the flower stigma. (ii) Second, pollen germination takes place on the stigma, developing a pollen tube down the style. (iii) Third, fertilisation happens when the male gamete reaches the ovule and fuses with the egg cell. (iv) Finally, this fusion results in the formation of a diploid zygote.
For more NCERT Solutions of Class 9 Science Exploration Chapter 11 Reproduction How Life Continues Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-11/
See lessAssertion (A): The zygote formed after fertilisation immediately attaches to the uterus wall. Reason (R): The uterus wall is always prepared to receive the zygote. (i) Both A and R are true and R is the correct explanation of A. (ii) Both A and R are true, but R is not the correct explanation of A. (iii) A is true, but R is false. (iv) A is false, but R is true.
The correct option is (iv) A is false, but R is true. Assertion A is false because the newly formed zygote divides mitotically into a multicellular embryo while moving down the fallopian tube over several days before implanting. Reason R is true because during every normal menstrual cycle, the uteriRead more
The correct option is (iv) A is false, but R is true. Assertion A is false because the newly formed zygote divides mitotically into a multicellular embryo while moving down the fallopian tube over several days before implanting. Reason R is true because during every normal menstrual cycle, the uterine lining thickens and enriches with blood vessels to receive a fertilized egg.
For more NCERT Solutions of Class 9 Science Exploration Chapter 11 Reproduction How Life Continues Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/science/exploration-chapter-11/
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