HELP! Physics accelaration.

Details are appreciated!

V - V Acceleration is defined as rate of change of velocity: a = - or v=v + at V - V t= starts from rest means v = 0; comes to a stop means v = 0 It is also possible to determine distance traveled (displacement) when time, initial speed and acceleration are known: d = v t+ 1/2 at If v = 0 then d = 1/2 at Solve for a: a = 2 (d - v t)/t- Solve for a: a = 2d/t- Solve for t: use quadratic - avoid going there! Solve for t: t = V2d/a The relationship which includes initial speed, final speed, acceleration and displacement is: V=v2+ 2ad If v = 0 then v = 2ad solve for a: a = =_ 2d solve for v : v = V( v -2ad) solve ford: d =v,-v 2a 1. A bullet accelerates at 6.8 x 10 m/s from rest as it travels the 0.80 m of the rifle barrel. What velocity does the bullet have as it leaves the barrel? 2. An airplane accelerates from a velocity of 21 m/s at the constant rate of 3.0m/s over +535 m. What is its final velocity? 3. The pilot stops (v = 0) the same plane in 484 m using a constant acceleration of -8.0 m/s . How fast was the plane moving before braking began (find v )4. An airplane must reach a velocity of 71 m/s (v ) for takeoff (v =0). If the runway is 1.0 km long (that's 1000 m) what must the constant acceleration be? 5. p. 83 How far does a plane fly in 15 s while its velocity is changing from 145 m/s to 75m/s at a uniform rate of acceleration? CP physics: acceleration #3 + 2ad