The inertia tag has no wiki summary.
20
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4answers
3k views
How does a mobile phone vibrate without any external force?
How does a mobile phone vibrate without any external force? By Newton's law, any body can't move without any external force
8
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3answers
147 views
Does Unruh Radiation replace the cosmic horizon radiation?
A recent paper, titled Inertia from an Asymmetric Casimir Effect, discusses the universal horizons relative to an accelerating observer (Rindler space). A figure it used to demonstrate its point ...
6
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3answers
2k views
Why is Higgs Boson given the name “The God Particle”?
Higgs Boson (messenger particle of Higgs field) accounts for inertial mass, not gravitational mass.
So, how could it account for formation of universe as we know it today? I think, gravity accounts ...
6
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1answer
143 views
How does liquid in a ball affect its rotational acceleration down a ramp?
Suppose we have a shell with mass $M$ and radius $R$. If we let that roll without slipping down a ramp of angle theta to the horizontal, we can easily find the acceleration of the shell the instant ...
5
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2answers
342 views
Are there 'higher order moments' in physics?
This may be a rather noob question but please let me clarify: I'm struggling to understand the use of the word 'moments' w.r.t., probability distributions. It seems after some research and poking ...
5
votes
4answers
251 views
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 ...
5
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0answers
43 views
What is the present state of Mach's Principle amongst physicists? [duplicate]
Possible Duplicate:
Is Mach’s Principle Wrong?
I'm doing research on gravitation and inertial forces and would like to know what is the place that Mach's Principle is occupying nowadays in ...
4
votes
2answers
190 views
In a spaceship, if a vessel suddently stops will an object inside the vessel keep going?
My question is a 2 part question.
First if a vessel in space is going very fast and suddently stops (maybe it is not possible but that is not the point) will things/humans inside the vessel keep ...
4
votes
2answers
279 views
Would a sneeze by a cosmonaut in a spacesuit affect his movement?
Naive question; feel free to shoot me down
It is a truism that any motion in space would continue indefinitely unless it is opposed by an external force. If a cosmonaut were to sneeze within his/her ...
4
votes
3answers
421 views
Infinite acceleration?
Why is acceleration regulated by mass? In a frictionless environment, why doesn't an object move at infinite acceleration if force is applied on it?
Force causes movement, so unless there is an ...
3
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2answers
496 views
Does Dark Matter interact with Higgs Field?
Dark matter does have gravitational mass as we know from its discovery. Does it have inertial mass?
2
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5answers
388 views
How would you improve braking capability on a hovercraft?
Pretty much letting my mind free-wheel.
Assume a fleet of air-supported hover-craft were to replace cars/etc on the streets. Assume also that the present traffic-signals/pedestrian rules remain ...
2
votes
2answers
156 views
London into Australia in 90 minutes
Me and my friend are having a debate on whether it would be possible for a human to travel at 15,000 miles an hour from London to Australia in the matter of 90 minutes. Would a human be able to ...
2
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3answers
307 views
The two faces of $F = m*a$
As I have understood,
$F(t)=m \cdot a(t)$
can have 2 different meanings:
When applying an external force $F$ on a point mass of mass $m$, the resulting acceleration of that mass at time $t$ is ...
2
votes
1answer
106 views
Is it humanly possible to change Earth's axis?
Just what the title states with the qualification that the change must be affected without using other celestial bodies as mentioned in the Clarke/Baxter SF 'Sunstorm'.
Obviously given the momentum ...
2
votes
2answers
79 views
Does inertia increase with speed?
I have heard that when the speed of the object increase, the mass of the object also increase. (Why does an object with higher speed gain more (relativistic) mass?)
So inertia which is related to ...
2
votes
2answers
125 views
Instability of a thrown tennis racquet
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 ...
2
votes
1answer
106 views
Why are there some inconsistencies with the underlying principle of center of gravity and rotational inertia?
COG: The lower the center of gravity, the more stable and object is.
Rotational Inertia: The farther the concentration of mass from the defined axis of rotation, the more resistance the object has to ...
2
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1answer
224 views
Double gyroscope: Can a spinning pencil tumble on only one axis?
Picture an object such as item 7 on this page .. http://en.wikipedia.org/wiki/List_of_moment_of_inertia_tensors
Call that the x axis and z is in to the distance. See diagram below.
We are in deep ...
2
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1answer
97 views
Pushing, inertia of a cart system
I have a cart with another cart on top which gets pulled down by another cart on the side. There is no friction.
The question is:
How strongly do I have to push with $F$ to keep the cart $m_1$ ...
1
vote
1answer
256 views
Kinetic Energy And Rotational Motion
The problem is, "A metal can containing condensed mushroom soup has mass 220 g, height 11.0 cm and diameter 6.38 cm. It is placed at rest on its side at the top of a 3.00-m-long incline that is at ...
1
vote
2answers
128 views
Fictitious Forces $\overset{?}{⇔}$ Constraint Forces (re: D'Alembert's Principle)
Are fictitious forces and constraint forces the same thing?
1
vote
2answers
1k views
Why does a ball bounce?
If an object is acted on by equal and opposite forces then it will be in equilibrium, and it's acceleration or velocity (and so direction as well) will not be changed.
So when a ball bounces, it ...
1
vote
2answers
408 views
Moment of inertia of a coin
I have a a coin infinitely thin, rotating along the diameter.
How to derive the formula for it's moment of inertia passing through the diameter.
I was suggested to use the surface density and ...
1
vote
0answers
44 views
Closed-form equation for orientation and angular velocity over time
If a rigid body, rotating freely in 3d, experiences no friction or other external forces and has an initially diagonal inertia matrix $\mathbf{I}_0$ (with $I_{11}>I_{22}>I_{33}>0$) and ...
1
vote
1answer
110 views
Force and Torque Question on an isolated system
If there's a rigid rod in space, and you give some external force perpendicular to the rod at one of the ends for a short time, what happens?
Specifically:
What dependence does the moment of inertia ...
1
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0answers
35 views
Calculate Rotational Intertia
If a can of soup, and a can of beans (tightly packed), are set in a race down a rough hill (has friction), the soup wins, because the inside of the can (soup) is not drawing energy from the system.
...
0
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3answers
101 views
Why is $F = mg - T$ in this case?
The situation is as follows:
I am told that $F_{net} = mg - T$ in this case, but doesn't that not take into account that $T$ isn't applied to the center of mass? Newton's second law is defined for ...
0
votes
1answer
931 views
Calculating Moment Of Inertia
The problem I am working on is:
A uniform, thin, solid door has height 2.10 m, width 0.835 m, and mass 24.0 kg.
(a) Find its moment of inertia for rotation on its hinges.
(b) Is any ...
0
votes
1answer
291 views
Finding Rotational Kinetic Energy Of A Clock
The problem I am working on is:
"Big Ben, the Parliament tower clock in London, has an hour hand 2.70 m long with a mass of 300 kg, and a minute hand 4.20 m long with a mass of 100 kg (see figure ...
0
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2answers
1k views
Jumping in an elevator?
I've always been under the impression that jumping in an elevator wouldn't help at all, especially after reading a snippet of physics where Einstein said that free fall was identical to zero gravity.
...
0
votes
2answers
2k views
Tensions And Pulleys With Masses
The problem I am working on is:
"A block of mass m1 = 1.80 kg and a block of mass m2 = 6.30 kg are connected by a massless string over a pulley in the shape of a solid disk having radius R = 0.250 m ...
0
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2answers
481 views
Torque And Moment Of Inertia
I am reading the two concepts mentioned in the title. According to the definition of torque and moment of inertia, it would appear that if I pushed on a door, with the axis of rotation centered about ...
0
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1answer
138 views
Two Different Sorts of Inertia: Inertial Mass and Moment of Inertia
There are two different sorts of inertia: inertial mass and moment of inertia.
I am currently reading about moment of inertia. Now, I know inertia is an important concept; with it, we can determine ...
0
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2answers
2k views
Why do objects with different masses fall at the same rate? [duplicate]
Possible Duplicate:
Confused about the role of mass
Today we were in our Literature class talking about the Renaissance and the Enlightement and our teacher also said that scientific ...
0
votes
2answers
181 views
inertia of a football and its angular momentum
What are the ways to create a mathematical model for the inertia of a football? Can the inertial of the football simplified to two cones stack against each other?
I'm trying to find the angular ...
0
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3answers
271 views
A man running on the treadmill
Imagine a man is running on a treadmill. His inertia with respect to floor will be zero because he is not moving with respect to floor. If both he and the tread mill suddenly stops he will not fall, ...
0
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1answer
77 views
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 ...
0
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0answers
168 views
Why Is Linear Inertia Only A Property? [closed]
The Inertia of a body is said to be its property or virtue that is directly proportional to its mass. Now if we consider Inertia of rectilinear motion, it depends on the mass as well as the ...
