Questions tagged [inertia]
Inertia is the tendency of a body to oppose changes to its state of motion. DO NOT USE THIS TAG for moment of inertia or inertia tensor!
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Is there a fundamental reason why gravitational mass is the same as inertial mass?
The principle of equivalence - that, locally, you can't distinguish between a uniform gravitational field and a non-inertial frame accelerating in the sense opposite to the gravitational field - is ...
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A Basic Question about Gravity, Inertia or Momentum or something along those lines
Why is it that if I'm sitting on a seat on a bus or train and its moving quite fast, I am able to throw something in the air and easily catch it? Why is it that I haven't moved 'past' the thing during ...
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Why does inertia happen?
In this video R P Feynman relates a story where his father told him that, even though we know the word "inertia" and what it means, nobody knows why inertia happens. Is that still true?
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Is Earth's orbit altered by recoil from take-off/launch/recovery of aero/space vehicles?
Just what the title states.
Pretty much all movement on Earth is by pushing against the much greater mass of Earth. Given there are easily thousands of aircraft taking flight/landing, and a lesser ...
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Definition of mass
In high school physics, I was taught that mass was just how much "stuff" or matter there is in an object. However, now that I am learning physics again in college, I am taught that mass of an object (...
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Does a box containing photons have more inertia than an empty box?
A box containing photons gravitates more strongly than an empty box, and thus the equivalence principle dictates that a box containing photons has more inertia than an empty box. The inescapable ...
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How can energy have inertia?
How can energy have inertia?
To my intuition, inertia is so closely associated with mass that my intuition says "Huh?"
Indirectly by mass energy equivalence it works fine, for example:
I have a ...
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Is there still no known origin of the law of inertia?
To quote Feynman at about the 21 minute mark of the first Messenger Lecture on The Character of Physical Law,
...that the motion to keep it going in a straight line has no known reason. The reason ...
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Inertia in an empty universe
I was reading a recent article on Mach's Principle. In it, the author talks about inertia in an empty universe. I'll quote some lines from the article:
Imagine a single body in an otherwise empty ...
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Physical meaning of the moment of inertia about an axis
In the context of rigid bodies, the inertia tensor is defined as the linear map that takes angular velocity to angular momentum, that is, the linear map $I : \mathbb{R}^3\to \mathbb{R}^3$ such that
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Instability of a thrown tennis racquet [duplicate]
Someone once mentioned to me that it's impossible to throw a tennis racquet (or similarly shaped object) into the air, perpendicularly to the string plane, in such a way that it won't turn.
What is ...
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Bidirectional jerk motion on a stopping vehicle
A stopping vehicle (say a car) has an apparent retardation (which may/may not be constant in magnitude) when force via brakes is applied.
I travel by subway trains, and I noticed an odd phenomenon. ...
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How does electron spin change instantaneously without violating inertia principle?
The inertia in one of the main properties of matter. That is why all process in macro world do not happen instantaneously.
What I do not understand is how we should apply this general idea of inertia ...
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Newton's first law: is his concept of (force of ) inertia still useful and used?
The force of inertia is the property common to all bodies that remain
in their state, either at rest or in motion, unless some external
cause is introduced to make them alter this state.
That is ...
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Do photons have inertia?
We all know the example where we say that a massless box containing photons has inertia, because the photons exert pressure of the inner walls of the box.
But my question is about a single photon ...
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