9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கற்கண்டு (இலக்கணம்) - தொடர் இலக்கணம், ஆகுபெயர் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -விரிவானம் (துணைப்பாடம்) - தாய்மைக்கு வறட்சி இல்லை! Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் -கவிதை பேழை (செய்யுள்) - மார்கழி பெருவிழா Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர்-இலக்கணம் - பகுபத உறுப்பிலக்கணம் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர் - இலக்கணம்-எழுத்து -அளபெடை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil அமுதென்று பேர்-துணைப்பாடம் - ஆறாம்திணை Important Questions And Answers Study Material - QB365 Set A

Published on: 16/06/2021
QB365 provides detailed and simple solution for every Book back Questions in class 9 Science Subject. It will helps to get more idea about question pattern in every book back questions with solution.
Download Tamil Nadu 9th Standard Science question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Science Test1.
How does the sound produced by a vibrating object in a medium reach your ears?
2.
Name the physical quantity whose SI unit is ‘hertz’. Define.
3.
What should an object do to produce sound?
4.
Name the device which is used to produce sound in laboratory experiments.
5.
The frequency of a source of sound is 600 Hz. Calculate the number of times it
vibrates in a minute?
1.
When object vibrate sound is produced, these vibrations cause the nearby molecules to vibrate. These vibrations are nothing but to and fro movement of particles. When these vibrations reach our ear we hear the sound.
2.
The number of vibrations (complete waves or cycles) produced in one second is called frequency. Its SI unit is hertz.
3.
An object should- vibrate to produce sound. The vibrating body causes the medium around it to vibrate.
4.
Tuning fork
5.
The frequency of 600Hz means that the source of sound vibrates 600 times in 1 second.
1 minute = 60 sec.
Number of vibrations in one second = 600
∴ Number of vibrations in 60 seconds = 60 x 600
= 36000
Hence the source of sound vibrates 36000 times in a minute.
9th Standard Syllabus & Materials
9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - திருக்குறள் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - மணிமேகலை Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உள்ளத்தின் சீர் - ஏறு தழுவுதல் Important Questions And Answers Study Material - QB365 Set A
NEW9th Standard
TN 9th Tamil உயிருக்கு வேர் - தண்ணீர் Important Questions And Answers Study Material - QB365 Set A
Tamilnadu Stateboard 9th Standard Subjects
Tamilnadu Stateboard Standards