Newtonian mechanics covers the discussion of the movement of classical bodies under the influence of forces by making use of Newton’s three laws. For more general discussion of energy, momentum conservation etc., use classical-mechanics, for Newton’s description of gravity, use newtonian-gravity.
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Physical meaning of force times area [duplicate]
Possible Duplicate:
What is the physical interpretation of force times area?
If force times area has any physical meaning, what would it be? Where would it be used?
I know that force ...
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1answer
113 views
Parabolic Motion
I was wondering if I was right about this simple problem:
A projectile is shot at an angle of 37.0° with the horizontal. The velocity of the projectile at its peak height is 16 m/s.
Then I was told ...
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3answers
427 views
Free falling objects
My teacher and I are in the middle of an argument because she says that if you were to drop two objects at the same time and the same height, but with different initial velocities, both of them would ...
3
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1answer
348 views
Coriolis force in free fall
Does the coriolis force has any measurable effect in free fall from large heights?
Take for example the sky diving experiment by F. Baumgartner who started from a height of about 40 km above New ...
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1answer
123 views
Opposing forces on an air cylinder
If an air cylinder is pushing two platens apart with a force of 100lbs, do the platens need to push back at 100lbs or 50lbs each to keep the cylinder from moving? Assume no friction and both platens ...
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3answers
287 views
Same momentum, different mass
The question is: if
A bowling ball and ping pong ball
are moving at same momentum
and you exert same force to stop each one
which will take a longer time? or some?
which will have a longer ...
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1answer
116 views
helium balloon tied to a car [closed]
A helium balloon is tied to the seat of a car. The doors and windows of the car is closed. If the car now starts moving, in which direction will the balloon move- front or back?
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2answers
644 views
Why I think tension should be twice the force in a tug of war
I'm going to provide my argument for why I think the tension in a rope should be twice the force exerted on either side of it.
First, let's consider a different example.
Say, there is a person named ...
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Other kind of Brachistochrone problem
We know the Brachistochrone problem that to find the shape of the curve down which a bead sliding from rest and accelerated by gravity will slip (without friction) from one point to another in the ...
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3answers
346 views
Jumping on earth versus jumping on the moon
Given the following problem:
On the moon the acceleration due to gravity is $g_m = 1.62 m/s^2$. On earth, a person of mass $m = 80 kg$ manages to jump $1.4 m$. Find the height this person will ...
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1answer
168 views
Bouncing Ball Pattern
If a ball is simply dropped, each time a ball bounces, it's height decreases in what appears to be an exponential rate.
Let's suppose that the ball is thrown horizontally instead of being simply ...
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0answers
77 views
Describing the movement of the object in a particular situation in Lagrangian way
Suppose there is a object M, (sliding motion) moving by the initial speed $v$ and the initial location $x_0$. Otherwise noted, friction is assumed to be nonexistent. It then meets a circular mold ...
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1answer
159 views
Questions regarding solving the Brachistochrone problem using Lagrangian
brachistochrone problem: Suppose that there is a rollercoaster. There is point 1 ($0,0$) and point 2 ($x_2, y_2)$. Point 1 is at the higher place when compared to the point 2, so the rollercoaster ...
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0answers
67 views
Stability of a rigid body spinning around minor, intermediate and major principal inertia axes [duplicate]
Possible Duplicate:
Instability of a thrown tennis racquet
Why does a cuboid spin stably around two axes but not the third?
I have a problem with one of my study questions for an oral ...
2
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1answer
219 views
Why are Euler's equations of motion coupled? Physical explanation
I have a problem with one of my study questions for an oral exam:
Euler’s equation of motion around the $z$ axis in two dimensions is $I_z\dot{\omega}_z = M_z$, whereas it in three dimensions is ...
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2answers
217 views
What are the reasons for leaving the dissipative energy term out of the Hamiltonian when writing the Lyapunov function?
I have a problem with one of my study questions for an oral exam:
The Hamiltonian of a nonlinear mechanical system, i.e. the sum of the kinetic and potential energies, is often used as a Lyapunov ...
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1answer
463 views
Friction due to air drag at high speeds
I am trying to set up this problem, but I am not sure how to go about doing so. (From University Physics, Young & Freedman):
You throw a baseball straight up. The drag force is proportional to
...
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4answers
147 views
Is a flawless trick die possible?
Trick dice have been used in gambling and magic shows. These are dice that, when rolled, will land with a preferred number facing upwards. This makes the result of rolling the dice non-random.
I was ...
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1answer
260 views
How does Baumgartner slow his velocity so that the parachute can open up?
How does Baumgartner slow his velocity so that the parachute can open up?
What is Baumgartner's speed just before his parachute opens?
What causes his speed to slow down just before the chute opens?
...
26
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6answers
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Could someone jump from the international space station and live?
Felix Baumgartner just completed his breathtaking free-fall skydiving jump from $120,000\,\text{feet} = 39\,\text{km}$ above the Earth, breaking the speed of sound during the process.
I was wondering ...
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votes
3answers
368 views
How to measure force of impact inside container?
I am in 7th grade and for my science fair project, I need a way to measure the force on a dropped object when it hits the ground. What I am trying to determine is which packing materials provide the ...
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4answers
2k views
How Felix Baumgartner has reached the speed of sound quickly
I have watched Felix Baumgartner freefall; but I wonder how Felix has reached the speed of sound quickly, in a matter of some seconds, then we had no idea of its speed?
Any explanation please.
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1answer
100 views
Time of a ball going up and down with air resistance
A ball is shot directly upward, and then it comes back to the place where it was shot. Suppose we have air resistance. Suppose $t_1$ is the time period from the moment that the ball was shot to the ...
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2answers
189 views
Does air resistance ever slow a particle down to zero velocity?
If a particle moves in a place with air resistance (but no other forces), will it ever reach a zero velocity in finite time? The air resistance is proportional to some power of velocity - $v^\alpha$, ...
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3answers
598 views
Why would a fat skydiver fall first in free fall?
I was having one of those obnoxious conversations with a friend where he was arguing that a fat skydiver would reach the ground faster than a skinny skydiver. To me it seemed as obvious that the world ...
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2answers
903 views
Norton's dome and its equation
Norton's dome is the curve $$h(r) = -\frac{2}{3g} r ^{3/2}.$$ Where $h$ is the height and $r$ is radial arc distance along the dome. The top of the dome is at $h = 0$.
Via Norton's web.
If we put ...
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2answers
322 views
Calculating force required to stop bungee jumper
Given that:
bungee jumper weighs 700N
jumps off from a height of 36m
needs to stop safely at 32m (4m above ground)
unstretched length of bungee cord is 25m
Whats the force required to stop the ...
3
votes
1answer
129 views
Angular acceleration of stone disk
I have a conceputal question regarding the following problem:
A round massive stone disk with diameter $0.600 m$ has a mass of $50.0 kg$. The stone rotates at an angular velocity of $115.2 rad/s$, ...
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2answers
100 views
A particle of charge $-e$ orbits a particle of charge $Ze$, what is its orbital frequency?
A point particle $P$ of charge $Ze$ is fixed at the origin in 3-dimensions, while a point particle $E$ of mass $m$ and charge $-e$ moves in the electric field of $P$.
I have the Newtonian equation of ...
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0answers
21 views
Helpful tutorials on force [duplicate]
Possible Duplicate:
List of good classical physics books
I'm having a hard time understanding force in my highschool AP physics class, i looked through youtube but without luck. Could ...
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2answers
227 views
Center of mass of a car
This might be little of the track but my question is more on possibility of application of principle of center of mass.
The probability of a vehicle overturning depends more on the level of center of ...
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1answer
317 views
Simple derivation of the tension of a cord on a suspended mass
Just wanted to disclaim this problem -- it is homework. However, I am not asking for the solution, I am wondering if anyone can tell me what I may be doing wrong in solving this specific tension ...
3
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1answer
372 views
Simple 2D Vehicle collision physics
I'm trying to create a simplified GTA 2 clone to learn. I'm onto vehicle collisions physics. The basic idea I would say is, To apply force F determined by vehicle A's position and velocity onto point ...
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0answers
196 views
What is the tension in the rope at that point? [closed]
A heavy ball with a weight of 120 is hung from the ceiling of a lecture hall on a 5.0--long rope. The ball is pulled to one side and released to swing as a pendulum, reaching a speed of 6.0 as it ...
4
votes
1answer
271 views
Lagrangian dynamics with initial conditions: motion of free particle
I am very new to Lagrangian dynamics so I am trying to get my head around the practical usage. So far on here all I could find were proofs and they did not make much sense to me, especially when time ...
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3answers
400 views
Newton's 3rd Law: How can I break things?
If I punch a wooden board hard enough and it breaks in two, has the board still exerted a force of equal magnitude on my fist?
When the board breaks in two due to my force, the halves have a ...
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1answer
281 views
Torque and equilibrium
I am a little stuck on the concept involved in part b) of the following problem:
A $5 m$ long road gate has a mass of $m = 15 kg$. The mass is evenly distributed in the gate. The gate is supported at ...
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2answers
102 views
How can thrust be generated in space which is a vacuum?
Since thrusters have no matter to push off of, how can a spacecraft generate thrust in the vacuum of space?
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1answer
160 views
How can the Air friction force be applied to an object?
Suppose we have an object and we throw it straight upward in the air. How do we apply the Air friction force to this object while moving upwards and after that downwards? Sorry if it's easy because ...
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2answers
220 views
is walking on ground identical to walking on treadmill
For the same speed and inclination, is the physics acting on the body equivalent? Lets assume the person keeps pace with something that moves perfectly uniformly.
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votes
3answers
261 views
Conservation of Energy in Different Frames of Reference
Say I have a bucket of fuel that can produce 150J of energy by combustion. No matter what frame of reference an observer or the bucket of fuel is in, since the configuration of molecules stay the ...
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1answer
331 views
Calculating torque in a structure
I posted this on math stack exchange but realize it is more a physics question.
I have a structure which is set up as shown in the image. A weight hangs from point A with mass $m$. Joint B is free ...
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0answers
21 views
What will be my motion inside earth [duplicate]
Possible Duplicate:
If it was possible to dig a hole that went from one side of the earth to the other
Suppose I drill a hole in earth through the centre and out from the other side. If I ...
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1answer
835 views
Are all central forces conservative? Wikipedia must be wrong
It might be just a simple definition problem but I learned in class that a central force does not necessarily need to be conservative and the German Wikipedia says so too. However, the English ...
1
vote
3answers
495 views
Is it possible to find out the distance traveled by a car if the force applied on it is given?
Say you have car which produces $F$ amount of force which is transferred to the wheels directly.
Now assuming that there is air friction which is causing a retarding force proportional to the ...
2
votes
4answers
996 views
Physics behind Wheel Slipping
Lets say that I'm in a car and I apply full acceleration suddenly. Now, the wheels would slip and hence the car doesn't displace much.
But If I start with some constant acceleration, slipping doesn't ...
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3answers
257 views
A chain 64 meters long whose mass is 20 kilograms is hanging [closed]
A chain 64 meters long whose mass is 20 kilograms is hanging over the edge of a tall building and does not touch the ground. How much work is required to lift the top 3 meters of the chain to the top ...
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0answers
269 views
Torque required to rotate a cement mixer..? [closed]
I need to design a motor to rotate a cement mixer which should mix one cubic meter. So, I calculated the required volume to be 1600 liters as it is an horizontal cylinder. Consider that the mixer ...
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2answers
1k views
Acceleration/tension of object. 1 on horizontal surface one hanging
A 5.00-kg object placed on a frictionless, horizontal
table is connected to a cable that passes over a pulley and
then is fastened to a hanging 9.00-kg object, as in Figure. Find
the ...
1
vote
1answer
554 views
Newton 2nd Law: Does vertical force (mass) affect the horizontal acceleration?
I learnt before that if 2 forces are perpendicular to each other, they should not affect each other. However in a recent experiment setup (asked in another question):
I believe the theoratical ...
