A rock is launched vertically upward. Let d1 be the distance traveled during the first second of the flight and d2 the distance traveled during the second second. What is the maximum possible ratio of d1/d2? What is the initial speed of the rock that corresponds to that maximum ratio? Neglect the air resistance and assume that the flight lasts longer than two seconds. The acceleration due to gravity is g.

The 2015-2016 season of Challenges had a strong finish, with many readers from all over the world submitting the solutions to our March, April, and May problems.

We are pleased to recognize the following contributors:

Guidelines for contributors:

Note: as always, we would very much appreciate reader-contributed original Challenges.

Boris Korsunsky, Column Editor

AAPT members receive access to The Physics Teacher and the American Journal of Physics as a member benefit. To learn more about this member benefit and becoming an AAPT member, visit the Joining AAPT page.