Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

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!

0
votes
1answer
26 views

Calculate stroke force and angle for a ball rolling on a surface to reach a destination position (optimal golf putt)

I'm trying to find an algorithm which calculates the optimal golf putt (angle, force) given a 3D surface (obtained through Poisson reconstruction), start and destination position (hole). I guess that ...
0
votes
0answers
9 views

Transfer of momentum from a wave to it’s waveguide based on theta and the inertia of the wave?

Bit of a complicated one - I've been trying to understand how the energy in a wave dissipates or transfers it's energy to the walls of a wave guide as the angle of the wave guide changes. As the ...
29
votes
5answers
3k views

Couldn't we always redefine units so that inertial mass and gravitational mass are equal?

It is a known fact that inertial and gravitational masses are the same thing, and therefore are numerically equal. This is not an obvious thing, since there are even experiments trying to find a ...
0
votes
5answers
150 views

If centrifugal force is fictitious, what force is real in its stead?

Here's an example illustration: The way I understand it, when the car starts turning, the centrifugal force at first does not exceed the force of friction, which allows the car to stir. But at some ...
1
vote
3answers
54 views

What is meant in mass' definition 'resistance to acceleration'? [closed]

Wikipedia: Mass is both a property of a physical body and a measure of its resistance to acceleration What does this mean? I know of the $E=mc^2$ formula. I think, the energy required to '...
0
votes
1answer
19 views

Why is Disturbance Force Equal to Total Force in Stokes Flow?

So this step confuses me. Why is it true that the disturbance force is the total force in stokes flow? Any advice or guidance would be great! From Pozrikidis' book:
0
votes
1answer
22 views

Calculating weight needed for a fixed pole

Imagine a game of swing ball, where the rope is 1m long, and the ball weighs 1kg. How do you calculate the weight that the pole has to be so it does not get pulled over, assuming it is not burried in ...
2
votes
2answers
90 views

How does inertia work at the particle level?

I've read recently that the mass of a proton is mostly not given by the Higgs mechanism. But rather it's given by the energy of quarks moving around inside the proton and gluons and other internal ...
0
votes
1answer
18 views

What's the seconde moment of a T beam with a heel?

the seconde moment of area of a rectangle is Iy = (bh^3)/12 b : base h : height What is the second moment of area of a T beam like this one ?
0
votes
1answer
33 views

Centrifuge Artificial Gravity?

I just saw the following video: NASA centrifuge. In video, a person is walking on a huge spinning centrifuge. But his weight is still acting downwards and there is no supporting force which will keep ...
1
vote
5answers
83 views

Inertial and non-inertial frame

How to define an inertial frame of reference mathematically? I want a definition with proper chosen coordinate axis which will help me to differentiate it with the non inertial ones. I have been ...
0
votes
2answers
59 views

Do the inertial mass and gravitational mass of an object depend on the frame of reference?

My understanding is that the "relativistic mass" of an object means any of the following three quantities (which are all identical): The "mass-energy", as defined by the formula $m = E / c^2$. The ...
1
vote
1answer
53 views

Faraday's Law and the Law of Inertia

Faraday's Law can be stated qualitatively as : Any loop (of wire) opposes/resists the change of magnetic flux through it. The Law of Inertia states that any physical object resists its change in ...
0
votes
1answer
40 views

Does buoyant force become less effective as acceleration increases?

Lets say a balloon with a certain amount of buoyant lift has a 2 kg mass strapped to it (including engines) and accelerates enough that it perceives a positive 2.5 g inertial force (2.5g * weight) ...
2
votes
1answer
41 views

Does potential energy increase inertial mass of system?

For example, we have a ball with mass m lying on the Earth. Then we lift it to a height h. So, now system Earth-ball have potential energy $E_p = mgh$. From Mass–energy equivalence system got $mass = \...
2
votes
1answer
57 views

Does the nucleus have less inertial mass than sum of inertial masses of constitute protons and neutrons?

In nuclear fusion part of nucleons' rest mass goes into radiation energy. Does it mean that inertial mass of result nucleus decreased?
1
vote
0answers
187 views

Does “Quantized Inertia Theory” violate conservation of momentum? [closed]

This recent news article reports that DARPA is doing work with "quantized inertia", despite their claim that it's not widely accepted by physicists: The Defense Advanced Research Projects Agency (...
1
vote
0answers
23 views

What is “Radiation damping stronger than inertia.”

I'm reading a paper on creating gamma rays in a lab and I've come across a phrase I simply don't understand; "Radiation Damping Stronger Than Inertia". As I understand it radiation damping is just ...
-4
votes
2answers
88 views

If there were no inertia would perpetual motion be possible? [closed]

Is it not inertia that makes a flywheel resist being put into motion? And if that is true, is inertia a consequence of being unable to create energy, i.e., why perpetual motion machines do not in fact ...
1
vote
0answers
47 views

The relation between mass, inertia and energy

I have trouble understanding the following concept: I learnt that mass is a measure of inertia, and that seemed logical enough. Yet separately I learnt that mass is a form of condensed energy. If ...
3
votes
2answers
195 views

Do electromagnetic fields have inertia? Or, what sets the speed of light?

In all mechanical waves, there is a restoring force and an inertial influence. For example, a plucked string oscillates because the restoring force brings it back to being straight and then the string'...
5
votes
2answers
335 views

How to find the axis with minimum moment of inertia?

If a system of particles is given, in a 2D plane, with particles having masses $M_1$, $M_2$, $M_3, \ldots M_n$ and coordinates $(x_1,y_1)$, $(x_2,y_2)$, $(x_3,y_3), \ldots (x_n y_n)$, then how can one ...
0
votes
1answer
65 views

Inertia when pulling on a rope [duplicate]

Imagine a fragile cord attached to a ceiling with its other side attached to a sphere. On the lower part another cord is atrached to the sphere. Now visualize you pull STRAIGHT downward on this cord. ...
0
votes
3answers
377 views

Difference between Mass and Inertia

My questions is about mass and Inertia, what is the difference between Mass and Inertia? Are they the same or different? How? I am really confused with it,some says mass is the measure of Inertia, ...
0
votes
1answer
84 views

Are mass or inertia the same thing, the same properties?

I think so. But I wold like to know another opinions to confirm.
0
votes
0answers
44 views

Mass or inertia value depends on the velocity c, or the stars? [duplicate]

Ernst Mach influenced the physicists of his time and also Einstein, asserting that the inertia of objects depended on the presence of distant stars. If there were no stars in the sky, the objects ...
0
votes
2answers
69 views

Overcoming the inertia of a body at rest

Neglecting friction and other forces (air resistance) and assuming all forces are orthogonal the gravity vector , consider a large dense sphere at rest on a perfectly flat plane which is plumb. Now ...
0
votes
2answers
57 views

Total energy of an object in motion in free space

In order to impart motion (additional motion) to an object in free space, inertia "soaks up" an given amount of energy prior to additional movement, which is related to its mass, irrespective of any ...
-2
votes
2answers
74 views

Can the origin of mass or inertia depend only of the gravitational field of matter? [closed]

The gravitacional field is directly proportional to mass or inertia. It doesn't have another property or field like this, with this power. I think that when we apply a force to an object, the ...
1
vote
1answer
42 views

Inertial stresses in Reynolds number

What is meant by the inertial stress in the definition of Reynolds number? Reynolds number = Inertial stress/ viscous stress
0
votes
2answers
99 views

Why do 2 bodies of different masses reach the ground at the same time? [duplicate]

Since inertia is the quantity that resists change in motion, and is represented by mass, and if two different objects are dropped from the same height, shouldn't the heavier mass accelerate less than ...
1
vote
0answers
97 views

How do I convert cardinal axis inertias to an arbitrary axis inertia?

I've tried to reduce this problem to the most basic form. I know the equation for a spring-mass system is generally: $$ F_{\mbox{applied}} = kx + m\ddot{x} \\ $$ but, in my case, I have a spring ...
0
votes
1answer
414 views

Explanation of the classic jerk and pull string system [duplicate]

It is known that when we jerk the bottom string quickly, it will break; and if we pull slowly the top string will break, while the force applied is the same. My confusion is: according to Newton's ...
9
votes
5answers
1k views

Inertia on a rotating disc?

If I toss a ball upwards in a train moving with uniform velocity, the ball will land right back in my hand. This is because the ball has inertia and it continues to move forward at the speed of train ...
0
votes
2answers
114 views

Gravity vs Electricity see-saw analogy and speed of light

Does electricity exhibit anything like the following steps: 1) A ball is rolled down from left side of a very long teeter-totter or see-saw 2) The see-saw rapidly (immediately) tilts once the ball ...
1
vote
3answers
94 views

Inertia as a fundamental interaction

Why is Inertia not included as one of the fundamental interactions, yet gravity is included as one of the four known interactions, and there is an equivalence established between gravity and inertia.
1
vote
1answer
142 views

Is Newton's third law due to inertia?

Newton's third law states that each force has an equal and opposite force. If I kicked a ball, it would apply the same force on me. Is this due to the ball's inertia? To clarify, is the ball exerting ...
2
votes
1answer
54 views

Inertia over an airplane [duplicate]

When an airplane is traveling, it moves at the same speed as the earth does due to inertia, but since, the plane is not directly touching the globe, how does is the speed of the earth is associated ...
0
votes
1answer
25 views

What happens when a electrically charged object is moving away from a charge it is attracted to(read description) [closed]

When a electrically charged object that carries momentum and inertia is attracted to a electrical field and is moving away from it, does it lose momentum as it is pulled towards it, or does it circle ...
0
votes
1answer
46 views

How to stop the propagation of waves?

I am trying to understand Newtonian equivalent law of inertia for the waves. Roughly Newton's law of inertia says that an object which is in motion in space will continue to remain in motion unless an ...
2
votes
2answers
252 views

Is a heavier baseball bat better than a lighter one?

Baseball season is coming up and I would like to know which bat is best for me. I think the heaviest bat I can swing good would be the best, but my brother thinks the lightest bat would be the best so ...
0
votes
3answers
108 views

Will anyone please explain this problem using 4 fundamental forces?

If there are only four fundamental forces (gravity,e.m.,strong,weak) in the universe and all other forces can be expressed as a function of them then consider this problem. Suppose I throw a particle '...
-1
votes
2answers
95 views

Inertial force in a bus [duplicate]

While i am standing in a bus that is accelerating an inertial force is acting on me in the direction opposite of acceleration (I understand that). But, what is the magnitude of that force.I thought it ...
0
votes
0answers
20 views

Can I model objects as point masses when calculating rotational inertia? [duplicate]

I have an aircraft. On it are weapons. Weapons have masses and centers of masses. The larger aircraft system has a center of mass. I wish to calculate the cumulative rotational inertia of only the ...
0
votes
0answers
41 views

Why a polyhedron with 3 different moments of inertia is stable when rotating on 2 of these and unstable on the other? [duplicate]

I have an object in which the main (principal?) moments of inertia are different one from another, in a way where $I_3>I_2>I_1$ which would be the case of a book, for example. If we have this ...
2
votes
1answer
111 views

Sciama's paper, On the origin of inertia

In his paper "On the origin of inertia", Sciama identifies $\frac{\Phi + \phi}{c^2} = -\frac{1}{G}$ This identity has confused me because I wonder how the right hand side arises since $\frac{\phi}{c^...
0
votes
1answer
140 views

Is the inertia of light equal to the inertia of mass under $E=mc^2$?

Under $E=mc^2$, 1kg of matter has $9\times 10^{10}$ joules of energy. So, if I had just the light shining from $9\times 10^8 $ 100 Watt light bulbs inside a perfectly reflective box, would that light ...
7
votes
4answers
2k views

What is the relationship between gravity and inertia?

What is the relationship between Gravity and Inertia? Einstein told us that gravity and inertia are identical. And from the fact that two different masses fall at the same rate, I believe we can say ...
0
votes
0answers
68 views

Physical significance of symmetric matrices and the inertia tensor

This is probably obvious, but I can't figure out why the inertia tensor (and many other tensors with some physical meaning, such as the conductivity tensor) are symmetric. Furthermore, what is the ...
0
votes
0answers
45 views

Stability of an object hanging on rotating string

I have read a statement that an on object hanging on a rotating string (like a ceiling fan), is stable against precession if moments of inertia on two perpendicular horizontal axes of the object are ...