Students may better prepare for the Class 10 board exams by using the material provided in the NCERT Solutions Science. This knowledge is extremely crucial as it assists students in better comprehending difficult subject matter. Checking how well you understand a certain subject by reading the solutions to the questions asked in the textbook is a great way to figure out where your knowledge is strongest and where it needs improvement. Our subject matter specialists have designed these NCERT Solutions for Class 10 Science in such a manner that the students will have a much better understanding of all of the subjects that are included in the curriculum for CBSE Class 10 Science.
Students are able to create a strong conceptual basis with the help of the NCERT Solutions PDFs available at SWC. This base plays a key part in the students’ preparation for the latter phases of the competitive examinations. We give comprehensive answers to challenges posed by NCERT in accordance with the methodology provided by CBSE. The students are able to effortlessly prepare all of the ideas that are presented in their respective courses better and more successfully, and they are even able to succeed in passing the most difficult competitive examinations, such as JEE Main, JEE Advanced, NEET, AIMS, and so on.
Your academic journey begins a new stage as you reach the eighth grade, and a new facet of learning awaits you. This is the year where pupils begin to acquire an interest in the topic at hand, and it is also the year in which you choose whether you will study business, humanity, or science in the following year (class 12). As a consequence of this, having a solid foundation of knowledge in fields such as mathematics and physics comes highly recommended. The NCERT textbook for class 8 is the greatest book now available on the market for enhancing one’s education in the areas of mathematics and science. Read up on the theory that is presented in the book for grade 8 and answer all of the questions that are posed in the practice section of the NCERT textbook.
When working through the exercises in the NCERT textbook, if you run into any type of difficulty or uncertainty, you may use the swc NCERT Solutions for class 8 as a point of reference. While you are reading the theory form textbook, it is imperative that you always have notes prepared. You should make an effort to understand things from the very beginning so that you may create a solid foundation in the topic. Use the NCERT as your parent book to ensure that you have a strong foundation. After you have finished reading the theoretical section of the textbook, you should go to additional reference books.
NCERT SOLUTION FOR CLASS 8 SCIENCE CHAPTER 13 SOUND – Exercises
Question 1. Choose the correct answer.
Sound can travel through
(d)Solids, liquids and gases
Solution : (d)air, liquid and solids
For the sound to travel it requires a medium. The medium can be solids, liquids and gases which provides the medium through which sound can travel.
Question 2. Voice of which of the following is likely to have minimum frequency?
Solution : (a) Baby girl.
Question 3. In the following statements, tick ‘T’ against those which are true, and “F” against those which are false.
(a) Sound cannot travel in vacuum. (T/F)
(b) The number of oscillations per second of a vibrating object is called its time period. (T/F)
(c) If the amplitude of vibration is large, sound is feeble. (T/F)
(d) For human ears, the audible range is 20 Hz. To 20,000 Hz. (T/F)
(e) The lower the frequency of vibration, the higher is the pitch. (T/F)
(f) Unwanted or unpleasant sound is termed as music. (T/F)
(g) Noise pollution may cause partial hearing impairment. (T/F)
Question 4. Fill in the blanks with suitable words.
(a) Time taken by an object to complete one oscillation is called ———-.
(b) Loudness is determined by the ————–.
(c) The unit of frequency is —————.
(d) Unwanted sound is called ————.
(e) Shrillness of a sound is determined by the ————- of vibration.
(a) Time taken by an object to complete one oscillation is calledtime period.
(b) Loudness is determined by the amplitude.
(c) The unit of frequency is hertz.
(d) Unwanted sound is called noise.
(e) Shrillness of a sound is determined by the pitch of vibration.
Question 5. A pendulum oscillates 40 times in 4 seconds. Find its time period and frequency.
No. of oscillations = 40.
Time- taken = 4 sec.
Frequency = no. of oscillation/ time-taken
= 40/4 = 10 Hz.
Question 6. The sound from a mosquito is produced when it vibrates its wings at an average rate of 500 vibrations per seconds. What is the time period of the vibration?
No- of vibration in 1 second = 500.
Therefore, frequency= 500Hz.
Time-period = 1/ frequency
= 1/500 = 0.002 second.
Question 7. Identify the part which vibrates to produce sound in the following intruments.
(a) Dholak is a musical instrument. Sound in dholak is produced by the vibrations of stretched membrane.
(b) Sitar is a musical instrument. It consists of stretched strings. When a string is plucked, it sets into vibrations and produces sound.
(c) Flute is a hollow pipe. When air is pumped into it, the column of air inside the pipe is set into vibrations. As a result, a pleasant sound is produced.
Question 8. What is the difference between noise and music? Can music become noise sometimes?
Solution : The sound that is pleasing to the ears is called music. For example, the sound produced by violins, pianos, flutes, pungs, etc.
The sound that is unpleasing to the ears is called noise.
Some examples of noise are as follows:
(i) Sound produced by horns of buses and trucks.
(ii) Sound of electrical generators.
(iii) Sound of a gun shot.
(iv) Sound produced by jackhammers.
Yes. Music can become noise when played at high volumes.
Question 9. List sources of noise pollution in your surroundings.
Solution : Noise pollution sources are:
(a) Bus and car horns.
(b) Firecrackers and loudspeakers.
(c) High volumes in televisions and transistors.
(d) mixers at home
(e) Bursting of crackers, and sound of big machines in the factories.
Question 10. Explain in what way noise pollution is harmful to humans.
Solution : There are many harmful effects of noise pollution on humans like:
(i) Lack of sleep.
(ii) High blood pressure (Hypertension).
(iii) Temporary or permanent impairment of hearing.
Question 11. Your parents are going to buy a house. They have been offered one on the roadside and another three lanes away from the roadside. Which house would you suggest your parents should buy? Explain your answer.
Solution : I would suggest my parents to buy a house three lanes away from the roadside because there would be more noise along the roadside produced by the vehicles. And the amount of noise will decrease as one move away from the roadside.
Question 12. Sketch larynx and explain its function in your own words.
Solution : A sketch of larynx is shown below:
Larynx is that part of throat which is responsible for producing sound. Inside larynx, there are two vocal cords, which are stretched across the voice box or larynx in such a way that it leaves a narrow slit between them for the passage of air. When we speak, air is forced into this small gap by the lungs which prompt vocal cords to vibrate. When the lungs force air through the slit, the vocal cords vibrate, producing sound.
Question 13. Lightning and thunder take place in the sky at the same time and at the same distance from us. Lightning is seen earlier and thunder is heard later. Can you explain?
Solution : The speed of sound is 330 m/s while that of light is 3 x 108 m/s. Thus, speed of light is much higher than the speed of sound. This is the reason light reaches us before sound during a lightning.
Conclusions for NCERT SOLUTION FOR CLASS 8 SCIENCE CHAPTER 13 SOUND
Lacking a solid understanding of scientific principles might have unimaginable repercussions. The NCERT textbook for class 8 science comes highly recommended from a number of different educators You will not only be able to improve your academic performance by using the appropriate combination of NCERT textbooks and NCERT answers for class 8 science chapter 13 but you will also be able to establish a strong foundation in science. The NCERT answers that were generated by the SWC team are among the finest solutions that are currently accessible on the web.