Question

A strobe-light series of pictures is taken of a red ball and a blue ball. The red ball was allowed to drop straight down, and the blue ball was given an initial horizontal velocity. Lines are drawn connecting each red ball image with the corresponding blue ball image. Describe the lines connecting the images.1) The lines slope down from the red ball to the corresponding blue ball.2) The lines slope up from the red ball to the corresponding blue ball.3) The lines are vertical.4) The lines are horizontal.

Answer 1

The lines are horizontal.

Horizontal velocity doesn't have any effect on the acceleration or speed of falling. In every picture, the red and the blue are both at the same HEIGHT, even though the blue one is pulling away horizontally.