Identify a suitable system undergoing a weight process, and determine whether a weight falls, stays put, or rises in bringing about the following changes.

(a) A tire pump is connected to a tire. e pump plunger is pushed down, forcing air into the tire. Assume that the walls of the tire, pump, and connecting tube are impervious to mater and perfectly insulating.

(b) A liquid fills a perfectly insulated rigid container. e liquid comes to rest from an initial state of turbulent motion.

(c) Hydrogen and oxygen are enclosed in a rigid container impermeable to mater and perfectly insulated. A spark (which may be considered infinitesimal and negligible) causes the two gases to combine.