The speed of a bullet as it travels down the barrel of a rifle toward the opening is given by v = (-5.70 107) t 2 + (2.15 105) t, where v is in meters per second and t is in seconds. the acceleration of the bullet just as it leaves the barrel is zero. (a) determine the acceleration and position of the bullet as a function of time when the bullet is in the barrel. (use t as necessary and round all numerical coefficients to exactly 3 significant figures.)

Very large accelerations can injure the body, especially if they last for a considerable length of time. one model used to gauge the likelihood of injury is the severity index ( ), defined as =/ . in the expression, is the duration of the accleration, but is not equal to the acceleration. rather, is a dimensionless constant that = the number of multiples of that the acceleration is equal to. in one set of studies of rear-end collisions, a person's velocity increases by 13.7 km/h with an acceleration of 36.0 m/s2 . let the + direction point in the direction the car is traveling. what is the severity index for the collision?