We are now going to start experimenting with a modified version of the virtual syringe model that will allow you to simulate applying upward and/or downward forces by drawing a force graph.
Watch the short video below that demonstrate how to draw an applied force vs. time graph in the model. Pay close attention to which part of the graph represents a push applied to the plunger, and which part represents a pull applied to the plunger.
Positive forces represent an external pull and negative represent an external push.