In one second the ball travels 4.9m. Graphs of velocity and position vs. time for the two balls are shown below. Galileo experimented with balls rolling down inclined planes, in order to reduce the acceleration along the plane and thus reduce the rate of descent of the balls. Suppose the angle that the inclined plane makes with the horizontal is q . How would you expect the acceleration along the plane to decrease as q decreases.
Acceleration is a vector.
The gravitational acceleration vector g is pointing straight down. Vectors can be written in terms of their components along the axes of a coordinate system. The object is constrained to move on the surface of the plane, and therefore will accelerate in the x-direction. We expect the magnitude of the acceleration to be equal to g x and to depend on q as sin q . A pebble is dropped into a water well, and the splash is heard 16s later.