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Cause of Coordinate Acceleration in Free Fall

The acceleration on a particle following a geodesic is defined by the Christoffel symbols which are in turn defined in terms of the metric. More properly, all inertially-moving objects not affected by ...
controlgroup's user avatar
3 votes
Accepted

Is the answer given in the option wrong?

The answer sheet is correct. You are ignoring the statement “The direction of the motion of the object changed only once, at time t.” That means that the velocity was zero at time t. So before time t ...
Dale's user avatar
  • 103k
2 votes

Issue with simplifying the equation related to non-uniform acceleration

The equation $$ \frac {d v}{dt}= A+ B\, v^2 $$ with constant $A$ and $B$ is an example of a Riccati equation. The Wikipedi article shows you how to solve it.
mike stone's user avatar
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1 vote

Do objects really "fall" at the same rate?

The effect you cite is so tiny as to be unmeasurable. This is why in most such calculations it is neglected with no loss in accuracy.
niels nielsen's user avatar
3 votes

Do objects really "fall" at the same rate?

You are right in that if you release from some height objects of different masses at different times, the acceleration relative to the surface (which moves with the planet) will depend on the mass of ...
Pato Galmarini's user avatar
0 votes

Confusion over what constitutes a uniform gravitational field in relativity

a. The Rindler coordinates are sometimes referred to as a "uniform gravitational field" because they have the property of not exhibiting any tidal-forces, like a classical uniform ...
NaiDoeShacks's user avatar
0 votes

Calculating vehicle and tire acceleration with tire slipping

I believe I've come up with the solution. What helped was separating out the wheels from the rest of the vehicle rather than treating them all as one in the FBD. Specifically, the tires are exerting ...
Gumgo's user avatar
  • 103
0 votes

Forces accelerating a tire

Just consider the forces on the wheel - ignore the forces exerted by the wheel on the ground. The four forces on the wheel are: (a) its weight - your downwards red arrow (b) the normal force from the ...
gandalf61's user avatar
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1 vote
Accepted

Forces accelerating a tire

I suggest a simple model to cover the no slipping and the slipping situation. Why don't the green and blue arrows simply cancel out, resulting in no acceleration/motion? Because the forces act on ...
Farcher's user avatar
  • 97.9k
0 votes

Why isn't a pseudo force considered for a block on an accelerating block?

When you analyze a system using $F=ma$ and $a$ is non-zero, that doesn't mean it is not an inertial frame. You are analyzing the motion from the "laboratory frame" attached to the floor, ...
RC_23's user avatar
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0 votes

What is the gravitational force acting on a massless body?

As the question points out correctly, mass cancels out leaving the acceleration; a=GM/r^2. Thus, massive or massless- it doesn’t matter. This was observed as far back as John Philoponus in the 6th ...
Riad's user avatar
  • 506
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Why should an electron falling into the nucleus, according to the Maxwell's laws of electrodynamics, destroy the atom?

It is often said in physics and chemistry classes and textbooks that atoms must be unstable when the electron continuously loses energy and finally fall into the nucleus according to classical physics....
Ohm's Lawman's user avatar
-1 votes

Why should an electron falling into the nucleus, according to the Maxwell's laws of electrodynamics, destroy the atom?

The protons and electrons do not annihilate. They combine to form neutrons. When a neutron star forms, the enormous pressure from a supernova explosion forces the electrons into the nucleus. The ...
KDP's user avatar
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0 votes

Why should an electron falling into the nucleus, according to the Maxwell's laws of electrodynamics, destroy the atom?

It is often said in physics and chemistry classes and textbooks that atoms must be unstable when the electron continuously loses energy and finally fall into the nucleus according to classical physics....
Ján Lalinský's user avatar
3 votes

Why should an electron falling into the nucleus, according to the Maxwell's laws of electrodynamics, destroy the atom?

They often give an impression that the two when combined would annihilate into energy. - No, that is not what is meant. Classically because the electrons are charged and accelerating, the electrons ...
Farcher's user avatar
  • 97.9k
1 vote

Does force cause acceleration or acceleration cause force?

Former philosophy student, current physics student here. This question is perfect since it pertains to the mathematical principles of natural philosophy. I can answer your question directly: it is ...
ConformalSymmetry's user avatar
0 votes

Newton's laws on constant velocity

In classical mechanics, the total mass of a closed system is conserved (constant). So necessarily $\frac{dm}{dt} = 0$, and the laws hold. In the case of a rocket, however, we might ignore the mass ...
ConformalSymmetry's user avatar
0 votes

Newton's laws on constant velocity

Whatever mass is being lost needs to be considered in the system. If the mass that's being lost is moving at the same speed, then the remaining mass must exert a force on it to accelerate it to that ...
Señor O's user avatar
  • 7,678
2 votes

$a=F/m$ is it possible?

Yes, we say forces cause acceleration, but from the effect (acceleration) we can reason back to the cause. You are right that the equality sign masks the relation of cause and effect, but that is just ...
ConformalSymmetry's user avatar

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