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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When a car accelerates relative to earth, why can't we say earth accelerates relative to car?
When a car moves away from a standstill, why do we say that the car has accelerated? Isn't it equally correct to say that the earth has accelerated in the reference frame of the car? What breaks the ...
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Very strange published papers on Mach's Principle
I have recently come across a set of peer-reviewed conference papers (https://petermarkjansson.com/research/machs-principle/) reporting observations of electromagnetic markers of Mach's Principle. In ...
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How to calculate HP knowing flywheel weight
So I've seen a guy on Youtube that has an RC nitro engine. He attached a quite big flywheel of known weight to its output, and then by measuring the time that it takes to reach max rpm he was able to ...
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How is Newton's first law of motion different from Galileo's law of inertia? If the two are the same, then why is the first law named after Newton?
Galileo's law of inertia (at least what I've learned) is
"A body moving with constant velocity will continue to move in this path in the absence of external forces".
And Newton's first law ...
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Moment of inertia of a rotating square toroid [closed]
I'm trying to work out the moment of inertia (i.e. what would be $I=mr^2$ for a point mass) of the volume of rotation around the y-axis of a square with side length a, at a radius along the x-axis R, ...
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Is there any relation between inertia and momentum?
Inertia is the that property of an object because of which that object resists a change in its state of rest or motion.
Momentum of an object is the product of mass and velocity, or its the quantity ...
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How does inertia forces depend on speed?
I was learning about Reynolds number in fluid mechanics and it is given as
$$Re= \frac{\rho V L}{u} $$
Physically, compares the inertia and viscous forces acting in a fluid.
I get that density will ...
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Could you determine if you were moving when standing on an infinite, frictionless plane?
I'm quite curious to know about this question. I don't really fully understand how inertia works so I couldn't quite put this one together in my head.
As far as I know, if you are moving in empty ...
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Why does the ball not climb the same height when released from a particular height in a double inclined plane even when the surface is frictionless? [closed]
According to the textbook, the ball will nearly climb the same height (a little less but never greater), why? I came across a question in SS Krotov where it was asked why does the ball not climb the ...
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If you could zero out your momentum, could you travel faster than the speed of light [closed]
I figure I'm going to get ridiculed for this question, and maybe deservedly so. The sensor images and eyewitness accounts from the Naval Aviators released last year of unexplained aerial phenomena ...
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What forces act on a car during cornering? (Forward inertia and centripetal force?)
I was testing the physics of an old car racing game on a completely flat, circular course. The game does not simulate downforce or lift, so we can imagine the test was conducted inside a vacuum:
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Are there any explanations for Inertia at atomic level? [closed]
At macroscopic level we can observe inertia. But what explanations are there for Inertia at molecular/atomic/quantum level?
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Does center of mass change in a complex rigid body if an element with negligible mass is removed?
If you are given an object composed of a sphere with two cylinders attached to opposite sides, and one cylinder is removed (cylinders has negligible mass) would the center of mass change?
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Why does rotational inertia represent the resistance of a body to angular acceleration
I understand how rotational inertia, $I=mr^2$, is defined based on $\tau_z=mr^2 \alpha_z$ as an analogy to the linear inertia $m$. But I'm still not sure why it represents the resistance of a body to ...
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Inertia and related concepts
I recently learned about inertia that it is a property by virtue of which body resists change in it's motion.
I want to know what does "resistance to change in motion" actually implies?
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Do objects need some time to know that the forces exerted on them are gone?
Okay, so I know how to solve this question, but I don't quite understand the concept behind it!
The solution simply states that the acceleration of m2 after the rope is cut will equal the force of ...
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Why does mass limit acceleration?
If a force of $10\,\mathrm{N}$ is applied to different objects of different mass in empty space, in the absence of gravity, why do lighter objects accelerate faster than heavier objects? Why does mass ...
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Consistency of premises in a reasoning regarding ( projectile) motion:on using( conterfactually)the inertia principle to determine the upward velocity
My question deals mainly with the reasoning used to solve the problem.
Suppose I know a projectile is moving in the XY plan and is sent at the origin with an initial velocity $v_i$ the vector of which ...
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Why did we expect gravitational mass and inertial mass to be different?
I've read many times that the fact that gravitational mass is equal to inertial mass (as far as we can tell) used to be a puzzle. I believe that Einstein explained this by showing that gravity is ...
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Why has the Higgs-field inertia?
The Higgs field is responsible for the masses of all elementary particles. Including the Higgs particle. But doesn't this transfer the question of mass, or inertia, to the Higgs field itself? Why has ...
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Trouble understanding the center of mass equation
I'm learning about center of mass, but I have trouble understanding the definition. How is $x_{com}=\frac{1}{M}\sum_{i=1}^{n}m_ix_i$ equal to $x_{com}=\frac{1}{M}\int xdm$?
At first I thought it ...
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Moment of inertia of a solid sphere; spot the mistake [closed]
What an I doing wrong?:
$I = \int r^2dm$
$M = \rho \frac{4}{3} \pi r³$
$dM = \rho \frac{4}{3} \pi 3r²dr = \rho 4 \pi r²dr$
$I = \rho 4π \int r^4dr = \rho 4π \frac{r^5}{5} = \frac{3Mr^2}{5} = \frac{3}{...
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Properties of inertia regarding soft boil egg and hard boil egg
If you have two spinning eggs on top of a table, and one of them is hard boiled and the other is raw, how can I analyze this from the perspective of inertia.
I'm asked to include the terms inertia, ...
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Mechanically speaking, how does inertia work?
(I haven't worked with this physics in decades, my terminology might be off)
First year varsity physics: Inertia is a property of mass. It is the amount of force to start an object moving (or change a ...
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Conceptual difficulty with friction and inertia
Consider this -
A box lies on the floor of a bus which starts accelerating. Two cases arise
$1.$ If the static friction is great enough, the box accelerates with the bus with acceleration equal to ...
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String, rod and inertia [closed]
I was recently reading through some posts on this site. A question struck me -
Why does an object attached to the end of a string which is further attached to an accelerating car behave differently ...
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Newton's $1$st law question
A long time since I posted it, still did not get a satisfactory solution. So I restate the problem -
Why does not an object attached to a string which is attached to the roof of an accelerating bus ...
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What is value of inertia of a box placed on the floor of an accelerating bus?
Apparently there is a lack of resources regarding inertia in the web. I have already asked 2 similar questions in this site, but still I have a problem with inertia. My question -
What is value of ...
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What would happen if an astronaut tried to swing a baseball bat in free fall?
I am interested in finding out how swinging a baseball bat or similar object would affect the astronaut's rotation in free fall, on the ISS for instance. How much would the astronaut swing the bat, ...
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Why does a body has inertia? [duplicate]
Today I asked a question on this site regarding inertia, and while reading one of the answers, a question popped up
Why does a body have inertia?
I looked up this site and several others, but could ...
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How does Inertial force arise?
Consider the following scenario$-$
A ball sits on the floor of a bus, which was originally at rest w.r.t the ground. Suddenly it accelerates forward, and we observe the ball moving backwards. Well, ...
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What factors influence the energy loss in a bounce?
Suppose a spherocylindrical solid is let to fall from some height to a flat, solid surface, bouncing some height up after it reaches the surface. The object clearly loses some of its energy due to the ...
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Electromagnetic inertial reaction force?
I accelerate charged particle $A$ causing virtual photons to travel to distant charged particle $B$ which feels an electromagnetic force proportional to $A$'s acceleration (for a classical field ...
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The definition of inertia in Mach's principle
Can anyone please explain me Mach's principle, i.e the definition of inertia he has given?
I am really not getting what spin and universe have to do with inertia because what we are taught in our ...
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What is the minimum force needed to overcome Inertia?
This question arose from this statement:
On Mars, weights would be different but the amount of force needed to overcome inertia would be the same.
The above statement was from Feynman lectures Vol.1 ...
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How does Inertia opposes change in state?
The first line of Wikipedia states that Inertia opposes change in velocity. My teachers also told that Inertia opposes change in state of rest or motion.
But I would like to know how?
Suppose a body ...
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Can we explain velocity without time? [closed]
I'm trying to wrap my head around inertia/velocity, or just change in general, I guess. I'm unsure exactly sure were my gap is, or what question to ask, so I'll explain with a scenario.
Lets say I'm ...
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Integral Issue for Inertia of Disk
I am currently following Taylor's "Classical Mechanics" and I am trying to understand creating the correct integrals to solve some problems related to the inertia of various shapes. I am to ...
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Is centripetal acceleration an inertial acceleration?
I am trying to understand what component of the force on an object moving in a regular bowl enables the ball to complete a "semi circle", without any external force being applied. Is the net ...
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What is the definition of mass?
From what I have seen so far, there seem to be two fundamental criteria for considering something to have mass:
First is that it must have inertia and therefore momentum,
Second is that it interacts ...
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Physics of pushing the top of a box a little bit to make it rock back and forth
Context:
I'm trying to make a simulation of a box that you can apply force to the top and it will oscillate back and forth until the energy in the system reaches equilibrium again.
Visual ...
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If inertia is affected by velocity, and velocity is relative, doesn't that mean that inertia is frame-dependent? [duplicate]
Here, by inertia, I mean the tendency of an object to retain its state of motion and resist change. Another way of defining inertia is how much force is needed to create a certain amount of ...
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Is inertia and gravity determined by relativistic mass or invariant mass?
As far as I know, mass fundamentally determines inertia and the gravitational force. But since there are two types of mass, which mass determines which? From what I have read so far, and correct me if ...
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Is inertia real reason for flow separation?
Consider airflow around square object, when an air particle A comes to the rear edge of an object. It is very logical that the particle would not turn at 90 degrees and follow back side of object, ...
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Is there a way to find out how long a body will glide after a force is applied once? [closed]
Can you tell how long a body will retain it's motion after being given a push from x amount of force (ex. 15 force applied, motion will last 18 seconds)?
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Is light affected by inertia?
A very popular way used by teachers to explain Einstein's theory that The speed of light is a Universal Constant, is to use an example as follows:
Two observers moving relative to each other [let's ...
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Why are roads sloped inwards in hills?
I recently noticed that the roads were sloped inwards at hills while taking a turn and a question jumped in my mind i understood that it is to provide centripetal force but if it isn't there why would ...
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Equivalence among three kinds of mass
If there are three kinds of mass
(1) resistance (classical inertial mass, rest mass)
(2) sensitivity to gravity (weight)
(3) creation of gravity,
the Eotvos experiment shows the proportionality ...
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When a car is coming to a stop is there any resistance offered by it to stay in motion?
Suppose a car is in a state of uniform motion moving at a high velocity and then begins slowing down due to force exerted by the brakes on the car. Will the car offer any resistance due to its inertia ...
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What is the gravity/inertia question?
Is the discussion about how gravity and inertia are the same, about the idea that when you hit a ball, it doesn't come back but when you throw a ball up, it does come back?
