A person throws a ball from height of 6 feet with an initial vertical velocity of 48 feet per second. Use the vertical motion
model, h = - - 16t2 + vt +s, where v is the initial velocity in
feet per second and s is the height in feet, to calculate the
amount of time the ball is in the air before it hits the ground
again. Round your answer to the nearest tenth if necessary.
time in air: seconds

3.1 s

Explanation:

use the quadratic formula

x = −b + √(b2 − 4ac)/2a

where a=-16 b=48 (the velocity) and c=6 (the height)

it's when something is going so fast it makes a loud noise, breaking the sound barrier, for example: a jet makes a loud noise, not only cause of the jet but because they reached a point where they went so fast that you can year the noise from various parts, kinda like a police car, lets say the car was going   so fast that you hear the siren of the cop car right next to you, but the car is probably a mile a way, it's cos the siren was next to you a few seconds if you understand me