Maharashtra Board Textbook Solutions
Standard 6 – Science
Chapter 13 – Sound
✨ 1. Fill in the blanks with the proper words.
(a) The propagation of sound does not occur through a vacuum.
(b) Noise pollution is a social issue.
(c) The sound which is disagreeable to the ears is called noise.
(d) Noise has adverse effects on our health.
❓ 2. What should we do?
(a) The silencer of a motorcycle is broken.
Ans:
(i) The silencer should be repaired immediately to reduce noise pollution.
(ii) The motorcycle should not be used until the silencer is fixed.
(b) A factory in the surroundings is producing continuous loud noise.
Ans:
(i) We should inform the factory authorities about the loud noise.
(ii) The factory owners should repair faulty machinery.
(iii) If no action is taken, we can lodge a complaint at the police station.
✍️ 3. Write the answers in your own words.
(a) What is meant by vibration?
Ans: Vibrations are the rapid to-and-fro movements (oscillations) of an object.
(b) Explain with the help of practical examples how sound is propagated through solids.
Ans: Sound travels through solids in the form of waves.
(i) If you place your ear on one end of a table and your friend taps the other end, you can hear the sound clearly. This shows that sound travels through the solid table.
(ii) A stethoscope is another example. Doctors use it to listen to heartbeats, showing that sound travels through solids.
(c) What is meant by noise pollution?
Ans: Noise pollution is the presence of excessive or unwanted sound in the environment, which can harm humans and other living beings.
(d) What measures will you take to control noise pollution?
Ans:
(i) Silencers should be installed in vehicles and machines.
(ii) We should keep the volume of television and music low.
(iii) The use of loudspeakers and horns should be minimized.
(iv) Vehicles and machines should be properly maintained.
(v) Factories should be located away from residential areas.
(vi) More trees should be planted as they help reduce noise.
📊 4. 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 | ✔ |