In physics the term velocity is always a vector. All that means is that it's got a direction with it. which also means this vehicle that was traveling in the east direction and then turned left is and is now , maybe traveling in a north direction. Making the guesses that the car was traveling due East and is now traveling due North, then the car has changed it's velocity by 40 m/s. By The Way do you happen to know how fast 40 m/s is? it's about 144 Kph :0 or about 90 MPH so this guy is also speeding :D, write him a ticket ... :P
