In a free-falling elevator, you can technically jump, but the experience would feel weightless due to the elevator falling at the same rate as you. Newton's third law applies, meaning if you push off the floor, you create an upward force on yourself. However, if you are in the middle of the elevator and cannot touch the sides, you would be unable to jump effectively. The sensation of weightlessness occurs because both you and the elevator are in free fall together. Overall, while jumping is possible, the context of your positioning within the elevator significantly affects the outcome.