Question

important question in chapter sound according to 9th class I don't need any useless answer​

Answer 1

Answer:

hey mate according to me...these are important...

• how is ultrasound used for cleaning explain how bats use ultrasonic waves to catch prey
• what what is sonar write its working in brief
• define define frequency amplitude wavelength and time period of a wave
• explain explain all the parts in an ear of well labelled diagram
• applications of ultrasound
• what is an echo and how is it different from reverberation
• what are the different types of range of hearing explain them....

hope they helped you.......

best of luck..

Answer 2

Answer:

I am u following u again and again because u r not coming online and this is what I meant to say that u never talk to me and that is what irritating me a lot ...now when u r not talking to me so I made one but she is my sis ... and one more thing that now I think that she is my first priority rather she shouldn't be it should be u but u r now frustating me the most at the last tempt.. I don't think now anything now could be happened....

BYE.....!!!!!! now that's in ur hand bye for today or forever

I am very dissapointed now