In a room with no windows, Zephyr and Phoenix are standing next to each other. Zephyr hangs a plumb line from the ceiling, which has a small weight at the bottom. The line hangs straight down, touching neither Zephyr nor Phoenix. If Zephyr begins to do a handstand, will the plumb line still remain out of touch from both Zephyr and Phoenix, and why?
Respond very briefly.
The plumb line will continue to hang straight down due to gravity, regardless of Zephyr's position. As Zephyr performs a handstand, her position relative to the plumb line changes, but the plumb line will still point towards the center of Earth. Therefore, unless Zephyr moves horizontally closer to the plumb line while going into or during the handstand, it will remain untouched by both Zephyr and Phoenix. Gravity will ensure the plumb line and weight remain pointing straight down, maintaining their original positions in the room.