Learn in your speed, with individual attention - Teachoo Maths 1-on-1 Class
Questions from inside the book
Question 1 Page 163
Question 2 Page 163 Important
Question 3 Page 163 Important
Question 1 Page 166 (Left)
Question 2 Page 166 (Left)
Question 1 Page 166 (Right Top) Important
Question 2 Page 166 (Right Top)
Question 3 Page 166 (Right Top)
Question 4 Page 166 (Right Top) Important
Question 1 Page 166 (Right Bottom) Important
Question 1 Page 167 Important
Question 1 Page 168 Important You are here
Question 1 Page 169 Important
Question 1 Page 170 Important
Question 2 Page 170 Important
Question 1 Page 172 Important Deleted for CBSE Board 2024 Exams
Questions from inside the book
Last updated at May 29, 2023 by Teachoo
Question 1 Page 168 An echo is heard in 3 s. What is the distance of the reflecting surface from the source, given that the speed of sound is 342 m s–1? Speed of sound = v = 342 m/s Time taken for hearing the echo = t = 3 s Let the total distance travelled by the sound = 2d Distance of the reflecting surface from the source = Total distance / 2 = 2d/2 = d Now, Speed of sound = (𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒 𝑡𝑟𝑎𝑣𝑒𝑙𝑙𝑒𝑑 𝑏𝑦 𝑠𝑜𝑢𝑛𝑑)/(𝑇𝑖𝑚𝑒 𝑇𝑎𝑘𝑒𝑛) v = 2𝑑/𝑡 v × t = 2d 2d = v × t d = (𝑣 × 𝑡)/2 d = (342 × 3)/2 d = 171 × 3 d = 513 m Distance between reflecting surface and source is 513 m