Final answer:
To make a baseball curve downward and towards the left, force must be applied to the ball so that it spins backwards with the top moving away from the pitcher and a slight tilt towards the left. This rotation creates a pressure differential via the Magnus effect, enabling the ball to curve in the desired direction.
Step-by-step explanation:
To achieve a curve or break in a baseball pitch that moves downward and towards the left (from a right-handed pitcher's perspective), force must be applied to the ball in a specific manner. The pitcher must grip the ball and execute a throwing motion that imparts both a forward velocity and a spin to the ball. The desired direction of rotation for the ball would be such that the top of the ball moves away from the pitcher and the side of the ball closest to the pitcher's body moves downwards. This backward spinning motion (relative to the direction of the pitch) combined with a slight tilt towards the desired direction creates what is known as a curveball.
In terms of physics, the spinning ball creates a pressure differential due to the Magnus effect, causing the air pressure to be higher on one side than the other, which results in the ball curving towards the lower pressure side. The direction and speed of the spin, combined with the velocity of the pitch and environmental factors like air resistance, determine the extent and sharpness of the curve.
In summary, to make a baseball curve downward and towards the left, the pitcher should apply a force on the ball that creates a backward spin (top moving away from the pitcher) with a slight tilt in the direction of the desired break.