# 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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### Disc deceleration with flexible shaft [closed]

If a disc with a large inertia is being driven at a constant speed via a flexible shaft, and a constant brake torque is applied to the end of the shaft (away from the disc), will the disc deceleration ...
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### Clarification on Momentum vs Inertia in Exerting Force when Stopping

I encountered a physics question in an exam four years ago that I believe may have had an incorrect answer key. I'm seeking clarification on the correct concept. The question was: The property of ...
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### Case study on inertia

When our upper body and lower body both are in contact with bus then after applying breaks why only upper body part moves forward?
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### Why do we have an opposing force in dynamic equilibrium? [duplicate]

I found this definition in my textbook about how dynamic equilibrium works. I was wondering if the opposing force is equal to the given force such that the net force is 0. Wouldn’t that mean that the ...
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### Why is the moment of inertia the rotational analog for mass and not inertia?

I've thought that both mass and the moment of inertia measure an object's inertia, one being in translational motion and the other in rotational motion. That has made complete sense to me, but in my ...
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### Why does binding energy of particles, which constitutes most of macroscopic mass, make them harder to accelerate?

I've seen a lot of questions on this topic so please don't misunderstand, I understand E = mc^2 and SEMF and so on. I specifically want to know how internal forces within lets say a nucleus make it ...
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### How does inertia affect an object suspended in a fluid?

When I asked my physics teacher how fully submerged objects are suspended in fluids, she told me it was because the object's density was equal to that of the fluid's as a result of the net force ...
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### Calibrating an inertial measurement unit (IMU) to zero/flat surface

I am building a digital spirit level using an inertial measurement unit (IMU), and I want to calibrate the device so that it shows the angle correctly. Does anybody here have experience with this kind ...
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### Using the principle of inertia to motivate the principle of least action?

Can we motivate the principle of least action with the principle of inertia that causes a mass particle to resist changes in its momentum? After all, the principle of inertia is the starting point and ...
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### Why are the masses hanging from a pulley not considered in its moment of inertia?

My physics textbook showed a diagram of a pulley with mass with 2 blocks hanging from either side by a massless string. They calculated the moment of inertia by finding an approximation of the pulley ...
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### Observational status of Sciama's hypothesis

I have always taken the existence of inertia more or less for granted, as an observational fact that does not require explanation. But on reflection this is an unscientific attitude, and perhaps there ...
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### What is happening on an atomic level (or lower) when a object is in motion (inertia)?

If you have an iron ball and throw it upwards you are imparting a force which opposes gravity. Initially this force is easily understood by your hand pushing the ball upwards, so the atoms in your ...
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### Propellant less propulsion when there is nothing to push against

Is there a way for a vehicle to move without losing mass when there is nothing for the vehicle to push against? For example, a helicopter flying around in a vacuum.
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### Inductance - a better analogy than the fact that it is similar to inertia

This question is to get a feel and good definition for what inductance actually is. I have read about the analogy where inductance can be compared to inertia-that the flux through an inductor resists ...
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### How are objects kept free falling in the LISA experiment?

I'm watching a video about the LISA experiment, which will be used to detect gravitational waves. In there, three space stations will be launched and will follow the Earth in its revolution around the ...
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### How do I convince my students the Newton's first Law is the way it is?

Every time I teach this law, there are always a few students asking me why a net force is zero on a system moving at a constant velocity. This group of students takes physics for the 1st time. It is ...
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### How density of fluids is would affect inertia?

I was watching that movie Event Horizon and they use water as an instrument to protect passengers of a space vessel from 30G acceleration, so my question is about a similar scenario, what would happen ...
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### Newton: an object in motion remains in motion: was there anyone else who believed this? [closed]

From my own experience as a schoolkid, that was the law that I was not buying. I could see his understanding of the Lunar orbit making him think this but otherwise, what in human experience would lead ...
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### Equivalence of Inertia and Gravity [duplicate]

I'm now wondering...does - energy=mass=inertia=gravity? Are they all, intrinsically, the same, "thing"; that is, the same, "entity".
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### How does classical, Newtonian inertia emerge from quantum mechanics?

From my understanding, inertia is typically taken as an axiom rather than something that can be explained by some deeper phenomenon. However, it's also my understanding that quantum mechanics must ...
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### How to mathematically express and then optimize my photon emitter? [closed]

A laser shoots photons directly at a flat disk with a fixed linear rate f(t) on the interval [t0=a,tn=b] with a horizontal path. E.x. f(t)=100 photons per second The laser is controlled by robotic ...
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