The discussion revolves around the concept of apparent weight in the context of a person in an upward-moving elevator that suddenly falls due to a broken cable. Participants explore the implications of free fall on the apparent weight experienced by the person.
The discussion is progressing with participants clarifying definitions and exploring the implications of free fall on apparent weight. There is acknowledgment of the correct interpretation regarding the absence of contact force during free fall.
Participants are navigating the definitions and implications of apparent weight, particularly in the context of a physics problem involving an elevator scenario. There is a focus on understanding the relationship between weight, normal force, and free fall conditions.
How would you personally define the term "apparent weight?"alaa amed said:Homework Statement
A person of weight w is in an upward-moving elevator when the cable suddenly breaks. What is the person's apparent weight immediately after the elevator starts to fall?
I think that's the key to answering the question, though I am not sure I interpreted properly. I think it means the weight relative to the force of gravity that acts on it in particular instance.Chestermiller said:How would you personally define the term "apparent weight?"
That's not correct. It means that, if he was standing on a scale, what the scale would read (i.e., the normal force the person would be exerting on the scale, and, by Newton's 3rd law, the normal force the scale would be exerting on the person). That's the definition of his apparent weight.alaa amed said:I think that's the key to answering the question, though I am not sure I interpreted properly. I think it means the weight relative to the force of gravity that acts on it in particular instance.
I think the person and the elevator would be free falling an so there would be no contact force?Chestermiller said:That's not correct. It means that, if he was standing on a scale, what the scale would read (i.e., the normal force the person would be exerting on the scale, and, by Newton's 3rd law, the normal force the scale would be exerting on the person). That's the definition of his apparent weight.
So, what is the normal force that the scale is exerting on the person if the elevator cable has been cut?
Yes. That is correct. So what does that mean regarding the "apparent weight" of the person, considering the apparent weight is equal to the contact force.alaa amed said:I think the person and the elevator would be free falling an so there would be no contact force?
It will be zero! Thank you so much for your help.Chestermiller said:Yes. That is correct. So what does that mean regarding the "apparent weight" of the person, considering the apparent weight is equal to the contact force.