jbriggs444's latest activity
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jbriggs444 replied to the thread Correct statement about random process of radioactive decay.An exponential distribution is an exponential distribution. The only difference is scale. I suspect that you are comparing the elapsed... -
jbriggs444 replied to the thread Correct statement about random process of radioactive decay.If you want the time between successive decays, you are concerned with an exponential distribution. One does then have a sampling...
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jbriggs444 reacted to A.T.'s post in the thread High School Thought Experiment: Behavior of shadow of object moving at speed c with
Agree.
I guess @Ibix refers to that fact that, if the object is very long (even when contracted), then you don't see both ends of its shadow... -
jbriggs444 reacted to A.T.'s post in the thread Undergrad Reference frames, center of rotation, etc with
Like.
But the same applies here: - For mere kinematics, any "center of revolution" is as good as another. - For dynamics, there are choices... -
jbriggs444 replied to the thread Undergrad Reference frames, center of rotation, etc.So yes, you are talking about the case of two or more objects orbitting one another. In that case we do not have a rigid body and the...
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jbriggs444 replied to the thread High School Thought Experiment: Behavior of shadow of object moving at speed c.If the screen and eye are stationary then it should not matter. The shadow of a flash will obviously be ephemeral. The illumination from...
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jbriggs444 replied to the thread Undergrad Reference frames, center of rotation, etc.I have never encountered the term "center of revolution" in the context of physics. Nor has Google, it seems. The references it found...
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jbriggs444 reacted to Ibix's post in the thread Undergrad Reference frames, center of rotation, etc with Like.
Not really, because the problem is that there are multiple ways to break the motion of a rigid body into rotation and translation, and...
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jbriggs444 replied to the thread Undergrad Properties of angular momentum.By contrast to a rotating frame of reference. It is not spinning. We may take it as an article of faith that any "frame" we speak of...
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jbriggs444 replied to the thread Undergrad Properties of angular momentum.I want to be sure that I understand the setup precisely. When you speak of "the" rest frame of the system's CoM, I believe that you are...
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jbriggs444 replied to the thread High School Trying to understand wind forces on a door.What I believe @russ_watters is getting at is that if the rest of the house is tightly sealed then no wind will enter the front door...
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jbriggs444 reacted to russ_watters's post in the thread High School Trying to understand wind forces on a door with Like.
Note that how hard it is to close a door in the scenario above depends on wind speed, direction, and how "tight" or "leaky" the building...
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jbriggs444 replied to the thread High School Trying to understand wind forces on a door.So, for instance, you are standing at your front door. The door is open and the wind is blowing into your house through the open door...
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jbriggs444 replied to the thread Happy Thanksgiving.We had our first Thanksgiving this year a week ago Thursday. Our away son had plans for Thanksgiving day, so we did it a week early. I...
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jbriggs444 reacted to A.T.'s post in the thread Undergrad Is calling fictitious forces "not real" just about terminology? with Like.
The problem with Newton's formulation is not that it is too brief, but rather the opposite: He should have skipped the initial prose...