Why sound needs medium for propagation? A particle oscillates 40 times in one minute what will be its time period of oscillations.
plz say me the answer
fast I will mark as brainliest

Explanation:

Sound needs a material medium for their propagation like solid, liquid or gas to travel because the molecules of solid, liquid and gases carry sound waves from one point to another. Sound cannot progress through the vacuum because the vacuum has no molecules which can vibrate and carry the sound waves.

Frequency= no. of oscillations/time=40/60sec

4/6=0.66

be subject to a force andchange its motion

what is the speed of a softball that travels 20m in 2secs

speed = 20/2 = 10 m/s