Suppose that you wanted to close a door by throwing a ball at the door. one ball will bounce off the door in a perfectly elastic collision while the other ball is made of clay and will stick to the door. each ball has the same mass and hits the door with the same velocity. which method will close the door quicker. explain.

Let f(x) = x4- 8x2 . find the relativeextrema of this function using the second derivative test.

For general projectile motion, when the projectile is at the highest point of its trajectory, its acceleration is zero? a)the horizontal and vertical components of its velocity are zero. b) its velocity is perpendicular to the acceleration. c)the horizontal component of its velocity is zero. d)its velocity and acceleration are both zero.

How do we measure or think of speed in the united states?