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alaa amed
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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?
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.
The weight of an object is determined by the force of gravity acting on it. At the moment of the fall, the person would be in a state of free-fall, meaning that there is no supporting force acting on them. This would result in their weight being zero.
Yes, it is possible for someone's weight to be zero at the moment of the fall. This can occur if the person is in a state of free-fall, meaning that there is no supporting force acting on them. In this case, their weight would be zero due to the absence of the force of gravity.
The main factor that contributes to someone's weight being zero at the moment of the fall is the absence of a supporting force. This can occur when an object is in a state of free-fall or when there is no contact between the object and a supporting surface. Additionally, the magnitude and direction of the gravitational force can also affect the weight of an object.
During a fall, the weight of an object remains constant. This is because the weight of an object is determined by the force of gravity acting on it, and this force does not change during a fall. However, the apparent weight of an object may change due to other forces, such as air resistance, acting on the object.
Weight and mass are often used interchangeably, but they are actually two different physical quantities. Mass refers to the amount of matter in an object, while weight is the measure of the force of gravity acting on an object. In the context of a fall, an object's mass remains constant, while its weight may change due to the force of gravity and other external forces acting on it.