13. Sound is a vibration that transfers energy from molecule to molecule. Which of the

following is the speed of sound of air at 20 degree Celsius?


A. 355 m/s . C. 343 m/s

B. 1144 m/s . D. 349 m/s



14. Sound waves propagate through different
mediums. When the temperature of a medium

increases, what happens to the speed of sound?


A. Increases . C. Remains the same

B. Decreases . D. None of them



15. What will be the speed of sound if the temperature of the air in degree Celsius is 40?


A. 345 m/s . C. 355 m/s

B. 325 m/s . D. 335 m/s​