A vector has an x-component of length of 3 and a y-component of length 4. What is the angle of the vector? (Hint: Use the inverse tangent)

tan theta = y / x = 4 / 3 = 1.33

arctan 1.33 = 53.1 deg  

-4 on

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