Redraw the following diagram to represent the situation (b) when work has been lost by the system.

Video transcript

Welcome back everyone. We need to consider the scenario below and illustrate what happens when work has been lost by the system at constant pressure. So recognize that pressure as the prompt states is a constant force. And recall that work is defined as our movement of our molecules in this case are molecules of gas against an opposing force. And so as the prompt states, we have work being lost by our system. In this case our system is the gas where the piston represents the boundary between our system and the surroundings being our walls of our container and the environment surrounding our container. And so if the system loses work, we would say that therefore work is going to be gained by the surroundings as we stated, our surroundings being the walls of our cylinder and the environment. And so with this understood if our system is losing work then work is going to be negative. And if work is negative, we want to recall that at constant pressure. Our volume is therefore going to be greater than zero. And so specifically our change in volume is going to be positive. So we can understand that our final volume should be greater than the initial volume of our system recall our formula which relates work to Constant pressure, where pressure is multiplied by -1 and multiplied by our change in volume. And so our image of our cylinder should now show a larger volume of our system, meaning we have our gas molecules more spaced out and our piston lying at a much higher level than initially. So actually let's draw it to scale so that it's easy to understand. So we have our piston here and sorry, we have our cylinder here. Where are piston? I'll define it as these red borders here and then we have our gas molecules. And let's actually draw this a bit higher. So let's say our piston is up here and we have our gas molecules more spread out. So notice that our measure of our gas molecules at their final at their final stage are at a much higher volume than the measure of our gas molecules initially, which have a much lower volume. And so we've successfully considered the illustration that occurs when work is lost by our system, which is going to be defined by our sketch here, which I'm boxing in yellow. So I hope that everything I went through is clear. If you have any questions, please leave them down below and I'll see everyone in the next practice video.