

NCERT Questions
Last updated at Dec. 16, 2024 by Teachoo
Transcript
NCERT Question 8 Two children are at opposite ends of an aluminum rod. One strikes the end of the rod with a stone. Find the ratio of times taken by the sound wave in air and in aluminum to reach the second child. Taking Speed of sound in air and aluminum from Table 12.1 NCERT Speed of sound in air = 346 m/s Speed of sound in aluminum = 6420 m/s Sound travels for the same distance in both cases. Let the distance travelled by sound = d We know that, Speed = ๐ท๐๐ ๐ก๐๐๐๐/๐๐๐๐ โด Time = ๐ท๐๐ ๐ก๐๐๐๐/๐๐๐๐๐ Air Time in air = ๐ท๐๐ ๐ก๐๐๐๐/(๐๐๐๐๐ ๐๐ ๐๐๐) = ๐/346 Aluminum Time in aluminum = ๐ท๐๐ ๐ก๐๐๐๐/(๐๐๐๐๐ ๐๐ ๐๐๐ข๐๐๐๐๐ข๐) = ๐/6420 Finding ratio (๐๐๐๐ ๐๐ ๐๐๐)/(๐๐๐๐ ๐๐ ๐๐๐ข๐๐๐๐๐ข๐) = ๐/346 รท๐/6420 (๐๐๐๐ ๐๐ ๐๐๐)/(๐๐๐๐ ๐๐ ๐๐๐ข๐๐๐๐๐ข๐) = ๐/346 ร 6420/๐ (๐๐๐๐ ๐๐ ๐๐๐)/(๐๐๐๐ ๐๐ ๐๐๐ข๐๐๐๐๐ข๐) = 6420/346 (๐๐๐๐ ๐๐ ๐๐๐)/(๐๐๐๐ ๐๐ ๐๐๐ข๐๐๐๐๐ข๐) = 3210/173 (๐๐๐๐ ๐๐ ๐๐๐)/(๐๐๐๐ ๐๐ ๐๐๐ข๐๐๐๐๐ข๐) = 18.55 Time in air = 18.55 ร Time in aluminum Hence, ratio is 18.55