Balbharati Class 8 General Science Solutions Sound

Welcome to NCTB Solutions. Here with this post we are going to help 8th class students for the Solutions of Balbharati Class 8 General Science Book Chapter 15, Sound. Here students can easily find step by step solutions of all the questions in Sound. Also our Expert Science Teacher’s solved all the problems with easily understandable language with proper guidance so that all the students can understand easily. Here in this post students will get chapter 15 solutions. Here all the Question Answer are based on Balbharati latest syllabus. Here all the question and answer are based on Maharashtra State Board latest syllabus.

Sound Exercise question Solutions :

Question no – (1)

Answer :

(a) The region in a sound wave, with higher pressure and density is called Compression and that with low pressure and density is called Rarefaction.

(b) Medium is Required for generation of sound.

(c) The total number of compressions and rarefactions produced per second in a sound wave is 1000. the frequency of the sound wave is “1000 Hz – as frequency is number of vibrations per second”.

(d) Different sound notes have different Frequencies.

(e) In loudspeaker Electrical energy is converted into Sound energy.

Question no – (2)

Answer :

(b) Astronauts on the moon cannot hear each other directly because on the moon there is no atmosphere to propagate sound wave.

(c) As the sound waves propagates in air, the air itself is not required to move from one place to another because sound is produced because of the transfer of energy between the air particles and not the movement of air molecules.

Question no – (3)

Answer :

In musical instruments like guitar the sound is produced by changing the tension on the string or by changing the vibrating length of the string which produces sound of different notes. This results is generation of different sounds. In musical instruments like flute sound is produced by blowing air in the holes while simultaneously changing the length of the vibrating air .This result in generation of different sounds.

Question no – (4)

Answer :

In a human larynx sound is produced by the passage of air through the vocal cords which makes it vibrate, different types of sound is produced by changing the tension on the vocal cord.

In a loudspeaker sound is produced when current is passed through the coil which creates a magnetic force, depending on the magnetic force the coil moves back and forth along with a conical screen. The movement of the screen with different frequencies and amplitude produces sound.

Question no – (6)

Answer :