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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What is the minimum acceleration that stops the rod from sliding in the frictionless surface? [closed]

What should be the block's acceleration 'a' such that the rod present inside, inclined at at the angle 'theta' and mass 'm' will be obstructed from sliding down. From car's frame of reference, a ...
0
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1answer
19 views

Acceleration of ball released from height H on a circular fixed wedge at its lowest point?

I've been facing a conceptual problem for quite some time. Suppose there is a fixed wedge.A ball of mass $m$ is released from a height $H$. The coefficient of friction on the surface is $μ$. ...
3
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2answers
77 views

Acceleration of a ramp

If we have a ramp and a block on it, and if all the surfaces are frictionless so both the the ramp and block can move. Is the normal force different from the time that ramp is not moving? If yes can ...
0
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0answers
19 views

Best learning of gyroscopic motion? [duplicate]

I crave to learn the nitty-gritty of attitude dynamics - namely I want to get really up close and personal with angular momentum, gyroscopic motion, non-inertial effects. I'm looking for a resource ...
2
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3answers
134 views

How can I calculate whether a shelf is strong enough to support a falling cat?

I'm building some shelves for my cat to climb on. The highest position the cat will be is 2 meters above the next shelf. The cat has a mass of 6.5kg. The shelf has a maximum load of 20kg. Using ...
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2answers
33 views

Weight added to truck [closed]

If weight is added to the back of a dump truck does the height of the truck decrease in direct proportion to the weight added - does weight added equal height decrease?
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2answers
101 views

Hooke's Law and Simple Harmonic Motion

Can anyone explain how the following formula is derived and what it means? $$x'' = -n^2x $$ I was reading through my high school physics textbook and I stumbled upon a section on Hooke's Law. It says ...
0
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1answer
61 views

Shape of water jet

Suppose you are shooting a water jet in a vacuum vertically onto a flat plate in a gravity-less room. The jet makes a right angle to the plate and water is assumed to be incompressible. The mass ...
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1answer
83 views

Acceleration orthogonal to movement direction

I've been told that acceleration orthogonal to an objects movement direction doesn't require energy. Thus when a satellite goes around the earth, the change in direction caused by gravity doesn't use ...
0
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2answers
31 views

Rod partially handing off edge of table

A uniform rigid rod of length $L$ lies at the edge of a frictionless table so length $x$ of the rod rests on the table and the rest is beyond its edge. Intuition suggests that the rod will stay like ...
1
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1answer
34 views

Rocket velocity during fuel burn [closed]

I know the formula for the velocity of a rocket after the on board fuel has been used up: $$ \Delta v = v_{ex} \ln\left( \frac{m_i}{m_e} \right) - gt $$ where: $v_{ex}$ is the exhaust velocity ...
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1answer
38 views

How to understand newton (unit of force)?

Simple question here for all of you, but I just wanted to form a mental image of the concept. I know the definition, but it's not 100% intuitive to me. So, I imagine 1 newton as force that I apply on ...
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1answer
41 views

Explanation about friction force directions of two moving bodies in contact

can someone explain me why in this scenario (picture below) we have a friction force Ftr12 in the same direction as movement (left part of the picture, case 1 ) and how these directions of friction ...
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6answers
110 views

A contradiction statement to $F=ma$ [closed]

If I thrown an object of mass 1 kg up in the air it will always fall with an acceleration of 9.8m/s. If I throw it very high up in the sky, it falls with a greater force as compared to if i throw it ...
0
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2answers
43 views

How did people discover the conservation of mechanical energy?

I want to write about the history of energy, and am focusing on mechanical energy at the moment. My question is: Can I attribute the conservation of mechanical energy to the power of maths, ...
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0answers
16 views

Creating a structural dynamic model using only modal test data

Short version: Suppose I excite a vibrational response in some structure and measure its mode shapes and natural frequencies. Is it possible to create a structural dynamic model of the structure ...
2
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3answers
95 views

Solving the two body problem numerically

I'm trying to solve the two body problem numerically, setting up $G$, $m1$ and $m2$ to be equal to 1. then I located each mass on positions -5 and 5 respectively along the $x$ axis and gave them both ...
1
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1answer
82 views

Newtonian motion of a particle confined to a smooth surface

Recently, I've been considering a model wherein a lone particle with constant mass m is confined to a surface $F$: $\mathbb{R}^m \to \mathbb{R}^n$ , where $m < n$. I declare this surface to be ...
2
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2answers
118 views

Why is Heisenberg uncertainty principle not valid in waves in string?

We know from high school physics that when the incident wave is traveling from a low density region (high wave speed) region towards a high density (low wave speed) region on a string, the width of ...
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1answer
49 views

How to understand tedious tension questions

A rope is wrapped $M$ whole turns round a cylindrical post, the two ends of the rope going in opposite directions. The coefficient of the friction between rope and post is 0.25. It is desired that ...
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2answers
40 views

Does the spring effect a moving ball? [closed]

There is a ball attached to spring which is streched out. The ball is held by a machine on the ground so it does not move, but when it is released it will quickly contract. At the same time a ...
0
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1answer
72 views

Consistent method for finding direction of static friction

I am having trouble coming up with a consistent method of determining the direction of static friction. So far the best I have come up with is: it should oppose the relative acceleration the contact ...
0
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1answer
54 views

Particle constrained to move in a sphere? [closed]

A particle of mass $m$ rests on the top of a smooth (frictionless) sphere of radius $R$. The particle is disturbed very slightly so that it starts to slide off the sphere, and its position can e ...
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2answers
69 views

Is torque still a vector in 2 Dimensions?

In 3D, torque is defined as $\vec{r} \times \vec{F}$ which is a vector, therefore having both a direction perpendicular to the plane of $\vec{F}$ and $\vec{r}$ and a magnitude of ...
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1answer
40 views

Boat Deceleration on Collision [closed]

I have a question regarding acceleration. When a boat collides with tires and they compress on contact and the boat is slowly brought to a stop, how is deceleration factored into this? As in, what ...
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3answers
157 views

Infinite acceleration

Let's say we have two planets at a stand still within reasonable distance of each other. They will accelerate towards each other and subsequently collide. If instead we give them a sufficient (but ...
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2answers
72 views

Kinetic friction with no force on an object

We've learnt that friction is the opposition of motion and that friction appears the instant a force is applied on an object i.e when an object is at rest (with no force acting on it) then there is no ...
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1answer
42 views

How is the final velocity in 2 body collision distributed between the 2 bodies?

Suppose 2 sphere of mass 1Kg move with velocity 5m/s and 10m/s in same direction. Let us call the ball moving with 5m/s blue and other one red with blue ahead of red from origin. Initial KE of Blue = ...
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4answers
89 views

Reduced-gravity flight (A300 0-G): what is actually reduced?

I doubt I can hide from the effects of gravity when I'm close to Earth. We usually don't question this biker is fully experimenting gravity: Source. But with the well-known "reduced gravity" ...
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3answers
47 views

Drag force - dimensional analysis

I have tried the following example from the link: MIT OCW 8.012 PS1 It is about dimensional analysis. Derive an expression for the drag force on a ball of radius $R$ and mass $M$ moving with ...
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3answers
56 views

Figure out the force constant of a spring [closed]

You are asked to design spring bumpers for the walls of a parking garage. A freely rolling 1200-kg var moving at 0.65m/s is to compress the spring no more than 0.090m before stopping. What should be ...
0
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2answers
48 views

Why are tensions in the pulley different when the pulley has a mass or moment of inertia?

When two blocks are connected by a string passing over a pulley whose moment of inertia is given (means pulley is not massless) then why does the string not have same tensions?
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0answers
43 views

Newtonian motion in vacuum

A spaceship is moving with constant acceleration in space. suddenly its fuel gets exhausted. Will it continue to move with constant acceleration and its velocity keep on increasing?
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66 views

Why is moment of inertia for a point same as a ring

The moment of inertia of a point and ring are both $m R^2$. It is interesting that the formula for moment of inertia is exactly the same for both. Is there any physical reason why this is the case? I ...
0
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1answer
57 views

On the connection between forces and the principle of stationary action

Feynman tries to account for the relation between the principle of stationary action, which is a statement about the whole path of a particle, and Newton's second law, which is a statement about the ...
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2answers
89 views

Intro Mechanics: Finding ball speeds after collision

So I'm reading about conservation of energy, momentum, balls colliding etc. and unsurprisingly there are hundreds of questions in my textbook where essentially they give me some of the variables (m1, ...
0
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1answer
34 views

Slingshot Energy into traveled distance [closed]

If I have a slingshot and I am told that when pulled it has about $E$ joules of energy, how do I compute the height at which an object of mass $m$ would travel if the slingshot is released in the ...
2
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2answers
40 views

Is sonic boom louder than the sounds that a object traveling at the speed of sound makes, if so why?

Here are the wave-front models for both: I am in an introductory physics course. Just learned about this. I am not entirely sure if sonic boom is louder. But from what I saw, it's loudness is ...
19
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6answers
3k views

Conical train wheels

I've been reading about how the conical shape of train wheels helps trains round turns without a differential. For those who are unfamiliar with the idea, the conical shape allows the wheels to shift ...
5
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3answers
278 views

Is it true that spring has more force acting on it at its positive maximum amplitude than than at the negative one?

Am I missing something? It seems obvious to me that at $+A$ and $-A$, the spring has restorative forces equal in magnitude but opposite in direction. But since gravity is always pulling it down, ...
1
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1answer
70 views

When we ride a bicycle, why do we tend to move left when we turn it right? [duplicate]

When we ride a bicycle, we tend to move our body left if we are taking a right turn and vice versa. Why is it like that?
-2
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2answers
66 views

Why do cylinders roll easily and not square or rectangular slabs? [duplicate]

Why do cylinders roll easily and not square or rectangular slabs?? Let us say both have same materiel and vertical dimensions? What is the reason for the slab always tends to slide?
2
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2answers
203 views

Showing that a mass moves a half cycle

Consider a mass $m$ at position $x(t)$ on a rough horizontal table attached to the origin by a spring with constant $k$ (restoring force $-kx$) and with a dry friction force $f$ $$\begin{cases} ...
1
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0answers
66 views

How to integrate this physics model? [closed]

OK, this might seem easy... but I'm having trouble solving it. Let's say I have a force acting on a body whose mass is known, by this law: $$F(t) = bt^2$$ where $b$ is a known constant, and $t$ is ...
3
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1answer
72 views

What makes us twist in a somersault?

In a backwards straight somersault you can decide whether you twist early or late. Twisting early means, that you induce the twisting movement before you rotatation hits 180° and twisting late means, ...
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2answers
57 views

Intitutive meaning the unit of Force $N$

I infer 1 Newton of force = 1 kg.m/ sec squared means a force if acting continuosly on a body at rest would make it gain an acceleration of 1 m/sec squared each second.So the change in velocity is 1-0 ...
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1answer
60 views

Can forces in N be thought of as a length? [closed]

A solid uniform 45.0 kg ball of diameter 32.0 cm is supported against a vertical friction-less wall using a thin 30 cm wire of negligible mass. (a)make a free body diagram for the ball and use it to ...
0
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2answers
76 views

Why are force, momentum, and kinetic energy derivatives of each other [closed]

Force $ma$ is the rate of change of momentum, or the derivative of momentum with respect to time $$\frac{d}{dt} mv = ma = F$$. Kinetic energy is the integral of momentum with respect to velocity: ...
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3answers
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In general, why do smaller guns have more felt recoil?

Why is recoil easier to control on a more massive gun compared to a smaller gun with the same bullet. Presumably the bullet leaves both guns with the same momentum, but the larger gun seems easier to ...
1
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1answer
60 views

Can mass-less spring system be solved?

Suppose we have typical chain of strings with masses, attached to the walls (W) at each side W-----m-----m--------W x=0 x=6 x=12 x=21 So if we let ...