This tag is for the classical concept of forces, i.e. the quantities causing an acceleration of a body. It expands to the strong/electroweak force only insofar as they act comparable to ‘classical’ forces. Use [tag:particle-physics] for decay channels due to forces and [tag:newtonian-mechanics] or ...

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101 views

Forces that fall under gravitational forces

I was explaining the air motion in the atmosphere, so I introduced Gravity, Pressure Gradient and Coriolis Forces. Then one of the Professors asked me this question, which I couldn't answer. He said ...
2
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2answers
626 views

Dielectric slab counter-intuitive formula?

For the calculation of force on one of the two equal(in magnitude, opposite in sign) point charges separated by $r$ with a dielectric slab of dielectric constant $K$ and width $d$ in between, the ...
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1answer
66 views

Why we get a force when a bus or car is going beside us? Is there any mathematical relation?

Suppose you are standing beside a road. A bus is running on the road, when it is crossing you, you feel a push of wind. Why its happen? Is there any mathematical relation?
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8answers
4k views

Do you feel gravity? [closed]

I have been reading a few articles about the question why we don't feel/notice gravity in everyday life, but I couldn't understand why exactly we don't feel/notice it, that is, why we don't feel a ...
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2answers
1k views

Different directions of frictional force when objects are rolling

My textbook has two instances of rolling bodies (smooth rolling). In the first, the body is rolling on the horizontal floor with some acceleration of its centre of mass. In this case, the book says ...
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2answers
153 views

What does the force mean in $dp/dt$ form?

One was to write Newton's laws is: $$F=\frac{dp}{dt}.$$ I don't understand what is the force there. I believe that $F$ is the net external force on the system. So supposedly I have a mass which is ...
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7answers
30k views

With Newton's third law, why are things capable of moving?

I've got a rather humiliating question considering newton's third law "If an object A exterts a force on object B, then object B exerts an equal but opposite force on object A" -> $F_1=-F_2$ ...
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4answers
618 views

Confused about Newton's 3rd law

I am confused about Newton's 3rd Law. If a person jumps off the ground a force is applied both to the person and to the ground. However, as $F=ma$ acceleration experienced by the Earth is much less ...
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2answers
428 views

Are there any non dissipative-non conservative forces?

Although the question stands for itself, I would like to know that if the answer has to be no then does any particular law forbids the existence of such forces; and if there are such forces then what ...
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3answers
162 views

Can two electrons attract each other?

Due to electrostatic repulsion the two electrons will repel each other as they both possess similar charges, lets leave gravitational attractive force out of the picture my question is can there be ...
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2answers
106 views

Is there a normal downward force here?

Now through my understanding, there is a weight force that points downward on block A, also another weight force that points downward on block B. Between block A and block B, there is two normal ...
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1answer
157 views

How is Magnetic force on a current carrying conductor $Blb$

I was reading an answer about torque acting on a rectangular current carrying loop kept in a uniform magnitude field B. Force acting on each sides is $F_1$, $F_2$, $F_3$, $F_4$. It's written here : ...
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1answer
174 views

Force of a solenoid on a ferromagnetic material

As I was trying to find an answer to another problem, I was informed that the equation I was using would not work. The equation I was using was $$F = (NI)^2\mu_0\frac{\text{Area}}{2g^2}$$ If this ...
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1answer
112 views

Inclined plane, circular motion and the friction

Suppose we have a cylinder on an inclined plane of mass $m$ and radius $R$ moving without sliding (so that $\varepsilon = a/R$). Why is the friction $F$ causing the circular motion sometimes lower ...
0
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1answer
36 views

Firing a blank vs live round from a gun [closed]

When firing a gun, is there any difference between a blank round and a live round, aside from the obvious presence of a bullet exiting the muzzle? For example, does it sound different? Is there any ...
0
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1answer
34 views

Work done by friction on a body?

I know that when a body slides over a surface, the work done by friction is not stored as potential energy in the body. It is dissipated in the form of heat. But why is it not stored as potential ...
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1answer
40 views

Question about force in transverse waves on a string

In deriving wave equation or power transmission of wave transmitted by a string, it is usually stated (with some assumptions) that the transverse force on a point of the string is proportional to the ...
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1answer
85 views

Forces Create Angular Acceleration And “Straight” Acceleration - But How Much Of Each?

Let me set up the following problem for a rectangle floating in space: We know its dimensions. We know its mass. There's a force pushing it for a known amount of time - we know the angle & ...
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1answer
170 views

Very confused about effective spring constant

I know that for springs in parallel, the effective spring constant is $k_1+k_2$ and for springs in series the constant is $1/(1/k_1+1/k_2)$. But there are some weird problems where finding the ...
3
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1answer
62 views

Help understanding work

I have this problem: An object with 800kg mass is lifted up 2.4m by a force $F$. How much work does the Force do on the object (gravity is the only other force acting on the object)? From what ...
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1answer
59 views

Can I convert Power to Force?

I just realized that I have some issues with physics: I cannot just convert Power to Force (different units), $P = F * v$. But am I not able to calculate the force on a car that accelerates with a ...
3
votes
1answer
323 views

Large deflection of cantilever beam

How can I find the amount of point force at the end of a cantilever plastic beam that produces e.g. 45° slope at the end of the beam? Is this the right equation: $$F=\frac{2EI\theta ^2}{L^2 ...
3
votes
2answers
176 views

How to use an accelerometer to correctly quantify the magnitude of vibrations

Consider the following setup: An accelerometer is placed inside a helicopter, measuring $g$ values along three axes $(x,y,z)$ every $10~\text{ms}$ (100 times a second), during a helicopter flight. ...
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2answers
57 views

Concept of a Magnetic Field

I was reading a physics book by some author and I got a little too confused with the explanation he stated about magnetic fields. A magnetic field is a field of force produced by current-carrying ...
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2answers
48 views

What is the meaning of this definition of potential energy?

The isolated system of particles is being observed. In the coursebook, $\vec F_\mu$ is by definition the vector sum of forces of all other particles acting on $\mu$-th particle. Usually, potential ...
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1answer
2k views

Why is the mechanical advantage of a wedge = length of slope/ width?

Mechanical advantage is defined as Force Output/Force Input For a symmetrical wedge with the length of the slopes being equal and the width being the distance between the end points, the articles ...
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2answers
85 views

Advantages of a deadblow hammer?

A deadblow hammer is a type of mallet with a hollow head filled with shot or sand. When you hit with it, say on an anvil, the mallet does not rebound, but just falls flat and heavy. I don't ...
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3answers
114 views

Why dont we consider force exerted by atmospheric pressure in mechanics?

My school has started teaching fluid mechanics, and it really bugs me why we don't consider force exerted by atmospheric pressure in mechanics. I couldn't understand a word my teacher said. There is ...
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0answers
32 views

How Newton's third law is involved in a tug of war? [duplicate]

Using Newton's third law, we can say that each team applies the same force on the opposite team. Then how one wins? Is it due to ground friction?
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1answer
29 views

Interaction Energy vs Force

I'm having a hard time determining the relationship/differences between interaction energy and forces. Say we have a system of two charged particles. Each particle will exert a force on each other ...
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3answers
505 views

How does this chair move?

I have a chair like this(shown in figure). I was kneeling on the part where we sit. I just gave a sudden push to the part where we rest the back, without moving my legs. I found that the chair is ...
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2answers
259 views

Good way to compute the force of a hammer blow?

What is a good and easy way to compute and/or measure the force of a hammer blow, not using any fancy or specialized equipment? If the hammer is swung by hand through an arc, it is not obvious to me ...
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1answer
49 views

A question on Newton`s laws of motion [closed]

Question: Let there be a monkey $B$ which is holding on to tail of the monkey $A$ which itself is climbing up a rope. The masses of monkey $A$ and monkey $B$ are $M$ and $m$ respectively.If $A$ can ...
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2answers
423 views

Why is force a localized vector and not a free vector?

A vector which is drawn parallel to a given vector through a specified point unlike free vector in space is called a localised vector. The effect of a force acting on a body depends not only on the ...
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2answers
41 views

Question on units for integrating F vs x graph

I had a homework problem with this graph of F(Newtons) vs x(meters). The graph has a straight line (constant slope) from (0,0) to (8,10). And the slope ((10-0)/(8-0)) came out to be 1.25, making the ...
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1answer
140 views

What are the equations for the weak and strong forces?

What are the equations for the strong and weak force, like how for the Electrostatics the equation is $F_c= k*Q*q/(r*r)$. I understand to an extend what the strong and weak forces are. However, I ...
4
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1answer
346 views

Why is the relationship between velocity and radius curved, in circular motion?

We are supposed to graph velocity squared against period. My instructor specifically said: The gradient of this graph is acceleration and We should observe a trend of decreasing orbital velocities ...
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0answers
21 views

Measurement of drag (?) tension between two surfaces

I want to know if there are (reasonably inexpensive) devices to measure the tension between two surfaces. Beware of my terminology: the first help I need is to actually formulate my question ...
1
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1answer
26 views

About friction contributing to speed

Friction in our daily experience is understood as a resisting parameter to the effort putted for moving an object on a surface. I understand friction as a negative force by describing what happens to ...
0
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1answer
70 views

How to prove using symmetry that electrostatic force acting parallel to the line joining two charges?

The unit vector $\hat{r}_{21}$ shows that the force is parallel to the line joing the charges. It could be otherwise unless space itself has some built-in directional property. . . This can be ...
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0answers
31 views

Why does every Action has a Reaction [duplicate]

I mean I know that when I exert a force on a wall the wall with exert it on me with the same force I did, but why, because of electron repulsion between my atoms and the wall's atom. I need to know ...
4
votes
4answers
242 views

Why perpendicular vectors do not share components?

I just can picture it in my mind or on paper. Can someone explain it with examples? This is the key idea behind the uniform circular motion: if the force has a component in direction of the object's ...
2
votes
2answers
698 views

How did Newton establish his famous third law of motion?

For every action,there is equal and opposite reaction . This is the famous Newton's third law of motion. But how did he come to this conclusion? We can prove 2nd law using calculus. But how did Newton ...
0
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2answers
72 views

Massless Pulley and direction of it's clamp

(clamp is perpendicular to the wall in the top right pulley system ) I have seen some diagrams similar to these . What are the forces on the massless and frictionless pulley in these situations ? ...
1
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0answers
40 views

Reaction forces

If a cyclic lamina (in equilibrium) is supported from two points that are of equal distance from the line joining the centre and the lowest point of the circle (so the arrangement is symmetrical ...
4
votes
2answers
340 views

Acceleration: A ball sliding down the inside of a semicircular bowl

Edit: To clarify, this is a homework question. But I couldn't care less about getting the answer to this specific question as it's not even assigned yet. It looks interesting and I want to understand ...
1
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0answers
29 views

Magnetic levitation project

For the past four years, I have been working on a project that will allow permanent magnets to levitate stably above a magnetic surface. So far I have tested my first theory which was to see if ...
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1answer
59 views

Weight of magnetic objects and polarization [closed]

I am an Iranian engineer and have a question which no one has answered me yet. In weighing a strong magnet, there is a difference between the weights from different polarization directions, why is ...
0
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0answers
28 views

Force between magnets with different sizes

I would like to know how to calculate pulling or pushing force between two the same shaped magnet but with different sizes. Specifically, I'm looking for cylindrical and bar magnets. I tried solve ...