Calculating elapsed time in different frames

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The discussion focuses on determining which frame measures the proper time interval between two events, emphasizing that proper time is measured in a frame where events occur at the same location. It is clarified that a stick, which measures events that are spatially separated, cannot constitute a proper frame. Instead, a person observing the events at the same position is considered the proper frame. The time measured by the person is expressed as T_me = T/γ, confirming the relationship between proper time and time measured in different frames. Overall, the conversation reinforces the concept of proper time in the context of special relativity.
Abhishek11235
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Homework Statement
Consider the following problem. A stick passes with speed v though a breadthless person whose(the stick) proper length is L. How does:

Stick See the time elapsed on my clock?

I see time elapsed on my clock?

The second part is easy. In my frame ,the stick is length contracted. So the time elapsed is ## T_{my}= L/\gamma v##

Now the first part. The stick measures the time L/v for the person to pass from one end of stick to another. The stick measures proper time of L/v. Hence he should see the time elapsed on my clock to be
##T_{me}= \gamma T= \gamma L/v##

However if I calculate using Lorentz transformation, I get same answer as in a. Where is flaw in my reasoning of 2? Thanks in advance
Relevant Equations
##T= \gamma T'##
The attempt is above
 
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Does the stick measure proper time?

In general, how do you decide which frame measures the proper time interval between two events?
 
TSny said:
Does the stick measure proper time?

In general, how do you decide which frame measures the proper time interval between two events?
If the 2 events occur are measured at same position ,it is proper frame. I think I got idea. Please correct me if I am wrong. In the frame of stick,the events(when the ends come and then pass through person) are spatially separated(by length L),the stick can't constitute proper frame. It is the person who is proper frame(he measures events occurring at same position). Hence the time should be ##T_{me}=T/\gamma##. Is it right?
 
Yes. Good.
 
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