A bullet emerges from a barrel of length 1 . 2 m with a speed of 640 m s - 1 . Assuming constant acceleration, the approximate time that is spent in the barrel after the gun is fired is

Step-by-step solution

Given, s = 1.2 m , v = 640 m s - 1 , a = ? , u = 0 ; t = ? We have the third equation of motion 2 a s = v 2 - u 2 2 a × 1.2 = 640 × 640 Or a = 8 × 64 × 10 3 3 And by first equation of motion v = u + a t Or t = v a = 15 4 × 10 - 3 = 3.75 × 10 - 3 s ≈ 4 m s