Textbook Solutions: Sound | General Science Class 6 (Maharashtra Board) PDF Download

 Page 1


Chapter 13: Sound 
 
 
EXERCISE [PAGE 96] 
Exercise | Q 1.1 | Page 96 
Fill in the blank with the proper word. 
The propagation of sound does not occur through a ______. 
 
SOLUTION 
The propagation of sound does not occur through a vacuum. 
Exercise | Q 1.2 | Page 96 
Fill in the blank with the proper word. 
Noise pollution is a ________ issue. 
 
SOLUTION 
Noise pollution is a social issue. 
Exercise | Q 1.3 | Page 96 
Fill in the blank with the proper word. 
The sound which is disagreeable to the ears is called ______. 
 
SOLUTION 
The sound which is disagreeable to the ears is called noise. 
Exercise | Q 1.4 | Page 96 
Fill in the blank with the proper word. 
Noise has adverse effects on our ________. 
 
SOLUTION 
Noise has adverse effects on our health.  
Exercise | Q 2.1 | Page 96 
What should we do? 
The silencer of a motorcycle is broken. 
 
SOLUTION 
If the silencer of a motorcycle is broken, then take the motorcycle to a mechanic and get 
it reinstalled or repaired. 
Exercise | Q 2.2 | Page 96 
What should we do? 
A factory in the surroundings is producing continuous loud noise. 
Page 2


Chapter 13: Sound 
 
 
EXERCISE [PAGE 96] 
Exercise | Q 1.1 | Page 96 
Fill in the blank with the proper word. 
The propagation of sound does not occur through a ______. 
 
SOLUTION 
The propagation of sound does not occur through a vacuum. 
Exercise | Q 1.2 | Page 96 
Fill in the blank with the proper word. 
Noise pollution is a ________ issue. 
 
SOLUTION 
Noise pollution is a social issue. 
Exercise | Q 1.3 | Page 96 
Fill in the blank with the proper word. 
The sound which is disagreeable to the ears is called ______. 
 
SOLUTION 
The sound which is disagreeable to the ears is called noise. 
Exercise | Q 1.4 | Page 96 
Fill in the blank with the proper word. 
Noise has adverse effects on our ________. 
 
SOLUTION 
Noise has adverse effects on our health.  
Exercise | Q 2.1 | Page 96 
What should we do? 
The silencer of a motorcycle is broken. 
 
SOLUTION 
If the silencer of a motorcycle is broken, then take the motorcycle to a mechanic and get 
it reinstalled or repaired. 
Exercise | Q 2.2 | Page 96 
What should we do? 
A factory in the surroundings is producing continuous loud noise. 
SOLUTION 
If a factory in the surroundings is producing continuous loud noise, then we can lodge a 
complaint against the factory to a local government body citing the troubles faced by the 
residents around and the danger it is causing to the environment. 
Exercise | Q 3.1 | Page 96 
Write the answer in your own words. 
What is meant by vibration? 
 
SOLUTION 
The to and from motion of a body about its mean position is known as vibration. 
Exercise | Q 3.2 | Page 96 
Write the answer in your own words. 
Explain with the help of practical examples how sound is propagated through solids. 
SOLUTION 
Sound is propagated in the form of waves in solids. It can be explained clearly from the 
below examples: 
• Place your ear on one end of a long table. Ask your friend to tap the table from 
the other end. You can hear the produced sound. Sound reaches your ear after 
travelling through the table. This indicates that sound can travel through solids 
and in the form of waves. 
• Stethoscope is another example of sound travelling through solids. Doctors use 
stethoscopes to listen to our heartbeat. 
 
Exercise | Q 3.3 | Page 96 
What is meant by noise pollution? 
 
SOLUTION 1 
The disturbance produced in the environment due to undesirable loud and harsh sound 
of level above 120 dB from the various sources such as loudspeaker, moving vehicles 
etc. is called noise pollution. 
SOLUTION 2 
Noise pollution is the excess of unwanted sound in the environment. It can adversely 
affect human and other living beings health.  
Exercise | Q 3.4 | Page 96 
Write the answer in your own words. 
What measures will you take to control noise pollution? 
Page 3


Chapter 13: Sound 
 
 
EXERCISE [PAGE 96] 
Exercise | Q 1.1 | Page 96 
Fill in the blank with the proper word. 
The propagation of sound does not occur through a ______. 
 
SOLUTION 
The propagation of sound does not occur through a vacuum. 
Exercise | Q 1.2 | Page 96 
Fill in the blank with the proper word. 
Noise pollution is a ________ issue. 
 
SOLUTION 
Noise pollution is a social issue. 
Exercise | Q 1.3 | Page 96 
Fill in the blank with the proper word. 
The sound which is disagreeable to the ears is called ______. 
 
SOLUTION 
The sound which is disagreeable to the ears is called noise. 
Exercise | Q 1.4 | Page 96 
Fill in the blank with the proper word. 
Noise has adverse effects on our ________. 
 
SOLUTION 
Noise has adverse effects on our health.  
Exercise | Q 2.1 | Page 96 
What should we do? 
The silencer of a motorcycle is broken. 
 
SOLUTION 
If the silencer of a motorcycle is broken, then take the motorcycle to a mechanic and get 
it reinstalled or repaired. 
Exercise | Q 2.2 | Page 96 
What should we do? 
A factory in the surroundings is producing continuous loud noise. 
SOLUTION 
If a factory in the surroundings is producing continuous loud noise, then we can lodge a 
complaint against the factory to a local government body citing the troubles faced by the 
residents around and the danger it is causing to the environment. 
Exercise | Q 3.1 | Page 96 
Write the answer in your own words. 
What is meant by vibration? 
 
SOLUTION 
The to and from motion of a body about its mean position is known as vibration. 
Exercise | Q 3.2 | Page 96 
Write the answer in your own words. 
Explain with the help of practical examples how sound is propagated through solids. 
SOLUTION 
Sound is propagated in the form of waves in solids. It can be explained clearly from the 
below examples: 
• Place your ear on one end of a long table. Ask your friend to tap the table from 
the other end. You can hear the produced sound. Sound reaches your ear after 
travelling through the table. This indicates that sound can travel through solids 
and in the form of waves. 
• Stethoscope is another example of sound travelling through solids. Doctors use 
stethoscopes to listen to our heartbeat. 
 
Exercise | Q 3.3 | Page 96 
What is meant by noise pollution? 
 
SOLUTION 1 
The disturbance produced in the environment due to undesirable loud and harsh sound 
of level above 120 dB from the various sources such as loudspeaker, moving vehicles 
etc. is called noise pollution. 
SOLUTION 2 
Noise pollution is the excess of unwanted sound in the environment. It can adversely 
affect human and other living beings health.  
Exercise | Q 3.4 | Page 96 
Write the answer in your own words. 
What measures will you take to control noise pollution? 
SOLUTION 
Following measures can be taken to control noise pollution: 
• To control noise pollution, we must control its source. Hence, silencers must be 
installed in vehicles such as motorcycles, cars, trucks, buses, and other noise 
producing machines. 
 
• We should watch television and listen to music at a low volume. Also, use of 
loudspeakers as well as horns of buses and trucks should be minimized. 
 
• Regular maintenance of automobiles should be done so that noise produced by 
them can be kept under check. 
 
• All industrial work should be done away from residential areas. 
 
• More trees should be planted in residential areas as they help in reducing noise. 
 
Exercise | Q 4 | Page 96 
Complete the table. 
 
Nature of sound Unpleasant Pleasant 
Speaking     
Whispering     
Aeroplane sounds     
Horns of Vehicles     
Railway Engine     
Rustling of leaves     
Neighing of a horse     
Ticking of a clock     
 
SOLUTION 
 
Nature of sound Unpleasant Pleasant 
Speaking   Pleasant 
Whispering   Pleasant 
Aeroplane sounds Unpleasant   
Page 4


Chapter 13: Sound 
 
 
EXERCISE [PAGE 96] 
Exercise | Q 1.1 | Page 96 
Fill in the blank with the proper word. 
The propagation of sound does not occur through a ______. 
 
SOLUTION 
The propagation of sound does not occur through a vacuum. 
Exercise | Q 1.2 | Page 96 
Fill in the blank with the proper word. 
Noise pollution is a ________ issue. 
 
SOLUTION 
Noise pollution is a social issue. 
Exercise | Q 1.3 | Page 96 
Fill in the blank with the proper word. 
The sound which is disagreeable to the ears is called ______. 
 
SOLUTION 
The sound which is disagreeable to the ears is called noise. 
Exercise | Q 1.4 | Page 96 
Fill in the blank with the proper word. 
Noise has adverse effects on our ________. 
 
SOLUTION 
Noise has adverse effects on our health.  
Exercise | Q 2.1 | Page 96 
What should we do? 
The silencer of a motorcycle is broken. 
 
SOLUTION 
If the silencer of a motorcycle is broken, then take the motorcycle to a mechanic and get 
it reinstalled or repaired. 
Exercise | Q 2.2 | Page 96 
What should we do? 
A factory in the surroundings is producing continuous loud noise. 
SOLUTION 
If a factory in the surroundings is producing continuous loud noise, then we can lodge a 
complaint against the factory to a local government body citing the troubles faced by the 
residents around and the danger it is causing to the environment. 
Exercise | Q 3.1 | Page 96 
Write the answer in your own words. 
What is meant by vibration? 
 
SOLUTION 
The to and from motion of a body about its mean position is known as vibration. 
Exercise | Q 3.2 | Page 96 
Write the answer in your own words. 
Explain with the help of practical examples how sound is propagated through solids. 
SOLUTION 
Sound is propagated in the form of waves in solids. It can be explained clearly from the 
below examples: 
• Place your ear on one end of a long table. Ask your friend to tap the table from 
the other end. You can hear the produced sound. Sound reaches your ear after 
travelling through the table. This indicates that sound can travel through solids 
and in the form of waves. 
• Stethoscope is another example of sound travelling through solids. Doctors use 
stethoscopes to listen to our heartbeat. 
 
Exercise | Q 3.3 | Page 96 
What is meant by noise pollution? 
 
SOLUTION 1 
The disturbance produced in the environment due to undesirable loud and harsh sound 
of level above 120 dB from the various sources such as loudspeaker, moving vehicles 
etc. is called noise pollution. 
SOLUTION 2 
Noise pollution is the excess of unwanted sound in the environment. It can adversely 
affect human and other living beings health.  
Exercise | Q 3.4 | Page 96 
Write the answer in your own words. 
What measures will you take to control noise pollution? 
SOLUTION 
Following measures can be taken to control noise pollution: 
• To control noise pollution, we must control its source. Hence, silencers must be 
installed in vehicles such as motorcycles, cars, trucks, buses, and other noise 
producing machines. 
 
• We should watch television and listen to music at a low volume. Also, use of 
loudspeakers as well as horns of buses and trucks should be minimized. 
 
• Regular maintenance of automobiles should be done so that noise produced by 
them can be kept under check. 
 
• All industrial work should be done away from residential areas. 
 
• More trees should be planted in residential areas as they help in reducing noise. 
 
Exercise | Q 4 | Page 96 
Complete the table. 
 
Nature of sound Unpleasant Pleasant 
Speaking     
Whispering     
Aeroplane sounds     
Horns of Vehicles     
Railway Engine     
Rustling of leaves     
Neighing of a horse     
Ticking of a clock     
 
SOLUTION 
 
Nature of sound Unpleasant Pleasant 
Speaking   Pleasant 
Whispering   Pleasant 
Aeroplane sounds Unpleasant   
Horns of Vehicles Unpleasant   
Railway Engine Unpleasant   
Rustling of leaves   Pleasant 
Neighing of a horse Unpleasant   
Ticking of a clock Unpleasant