jbriggs444's latest activity
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jbriggs444 reacted to Steve4Physics's post in the thread Correct statement about size of wire to produce larger extension with
Like.
Here's one way to look at it... For a given material, there is a unique maximum value of strain, ##\epsilon_{max}##, at which fracture... -
jbriggs444 reacted to haruspex's post in the thread Correct statement about size of wire to produce larger extension with Like.
The given answer does not require exact linearity.
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jbriggs444 replied to the thread High School A Mind-Boggling Number Comparison.Given a set of all sets, one can define the set of all sets not containing themselves. Then you ask yourself, does this set contain...
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jbriggs444 reacted to Herman Trivilino's post in the thread High School Limiting case for an Atwood's machine with Like.
Only in the limiting case where ##m_1## is zero. In other words, you have an ideal pulley and you hang two objects such that the mass...
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jbriggs444 reacted to brotherbobby's post in the thread High School Limiting case for an Atwood's machine with Like.
If you put the value of the tension ##2T = \dfrac{4m_1m_2}{m_1+m_2}g## and subtract it from the force due to gravity ##(m_1+m_2)g##, it...
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jbriggs444 replied to the thread High School Limiting case for an Atwood's machine.Right. That external agent is, of course, the tension in the rope. Right. The center of mass of the two masses is accelerating...
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jbriggs444 replied to the thread High School Limiting case for an Atwood's machine.Accelerating upward at 1g is different from freely falling downward at 1g. One requires an external force. The other does not.
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jbriggs444 replied to the thread High School Limiting case for an Atwood's machine.Right. That was a braino in my original. Corrected now. Apparently you read it before I fixed it. If you go up with an acceleration of...
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jbriggs444 replied to the thread High School Limiting case for an Atwood's machine.In that situation, mass ##m_2## is approximately freely falling while mass ##m_1## is approximately accelerating upward at ##g##. Of...
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jbriggs444 replied to the thread Undergrad Reference frames, center of rotation, etc.That is not a substantive response. Since you are not interested in a genuine discussion, I am out. Unattributed straw men devoid of...
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jbriggs444 replied to the thread Undergrad Reference frames, center of rotation, etc.You are invoking the formula for centripetal acceleration, ##a = \frac{v^2}{r}##, I suppose. That formula does not apply to rotation...
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jbriggs444 replied to the thread Undergrad Reference frames, center of rotation, etc.One can choose a center at B without choosing a coordinate system where B is moving along a straight line trajectory at constant speed...
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jbriggs444 reacted to A.T.'s post in the thread Undergrad Reference frames, center of rotation, etc with Like.
The way to clear up that confusion is to learn the math, not endlessly go on about what your eyes see. Or you just forget about it and...
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jbriggs444 reacted to Dale's post in the thread Undergrad Reference frames, center of rotation, etc with Like.
Because the distance between the primary and the satellite can change. And if they are not both tidally locked then the distance between...
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jbriggs444 replied to the thread Undergrad Reference frames, center of rotation, etc.EDIT: The quoted passage above has been removed from the post in which it appeared. The next few paragraphs are now unmotivated. So I've...