The number of work movements between pieces of equipment is indicated on:

A cross chart effectively represents the number of work movements between pieces of equipment, illustrating the interactions and flow of materials or tasks between various workstations. This type of chart highlights how often equipment is utilized in conjunction with one another, aiding in identifying bottlenecks, optimizing workflows, and enhancing overall efficiency within a production process.

In contrast, other choices serve different purposes. A flow diagram primarily visualizes the sequence of steps in a process, focusing on the path of materials rather than specific movements between equipment. A Gantt chart is used for scheduling tasks over time and does not provide insights into equipment interactions. Johari's window is a tool used in communication and personal development, unrelated to operational efficiency or equipment movement tracking.