2. sound?(b) Describe so3. Describe howfrom the souromedium4. Describe an e(a) very loud(c) weak sound1. An electric bell is suspended in a bell jar andthen air is removed from it. On switching on(d) no sound is heard2. The convenient instrument used in laboratory3. The crack of a thunder cloud is heard laterD. Tick (m) the most appropriate answerthe electric bell, the sound heard is:(b) normal soundto produce pure sound is :(a) whistle(b) drum(c) tuning fork(d) guitarthan the flash of lightning because, the lighttravels :SOME COMMAmplitude,three importantAmplitudebody from itsis metre (m)(a) much slower than sound(b) much faster than sound(c) at the same speed as sound(d) none of these4. The approximate speed of sound in air atroom temperature is :(a) 33.2 ms-1(b) 3320 ms -1(c) 3.32 ms-1(d) 332 ms-1In figureFrequenoin one seconIts SI UHeinrich R.second, its fTimecompleteSI unit is5. An observer puts ear on a railway line500 m from a friend with a hammer. Whenhis friend hits the railway line with thehammer, the observer hears two sounds,The sound is first heard through:(a) railway line(b) air(c) at the same time through railway lineand air(d) no sound is heard​