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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1answer
28 views

How does string tension influence the harmonic spectrum?

Hey there fellow physicists & musicians! I have a question both physics and music related. How does the string tension affect the sound spectrum? More precisely, how do the respective ...
1
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2answers
75 views

Model/formula for bouncing ball

I'm programming an animation of a bouncing ball, and I want it to be as realistic as possible. I fully understand the physics while the ball is rising and falling: It accelerates downward at 9.8 ...
1
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3answers
68 views

What is the relation between Force, Physical Strength,Enery and Work?

I am sorry ,but, I am not much of science or a physics guy, if this question sounds stupid. Anyways, what is the relation between all of them. Like for example, does applying more force means more ...
1
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2answers
84 views

Shelf always tipping over when pushed, thanks to normal force

A while ago, I encountered a problem with a person pushing a shelf at the top, with the center of mass located in the middle. The task is to find the maximum magnitude of the force vector, not causing ...
-1
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1answer
37 views

Non-uniform Normal force, friction

I got problems understanding the Non-uniform normal force. Why is it non-uniform? Because the object would have different densities in different parts, so weight would be greater in some parts? So ...
7
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5answers
136 views

Astronauts on a tether

Recently, I went to a competition with a science test. One of the questions was as follows: Two astronauts (A and B) are tethered together in space. Simultaneously, Astronaut A pulls on the tether ...
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1answer
68 views

Does Newton's third law remain totally unchanged even in Einstein's theory?

Why Newton's third law remain unchanged still now in relativity theory (as for example that is why we feel weight due to equal but opposite reaction of the Earth's surface)?
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2answers
80 views

How do we define what is “External” force or “Internal” force in the context of momentum conservation?

I know that without presence of any "External" force momentum is always conserved. But how do we distinguish between "External" force and "Internal" force where all are "Force"?
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2answers
34 views

How to prove that the potential of a conservative central force depends only on the magnitude of the distance & not on the direction of the vector?

If a conservative central force acts on a body then its potential only depends on the magnitude of the distance between two bodies (does not depend on direction of vector). Is there any proof of it ...
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0answers
54 views

Why Newton's gravitational constant remains unchanged in relativity though gravity is not a force?

I know that Einstein described gravity as a curvature of spacetime. So, It is not a "force" but why Einstein had to accept Newton's gravitational force constant?
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1answer
29 views

Torque on a charged ring

I have been studying electromagnetic induction. As I understand, a magnetic field will exert a force on a moving charge. What I would like to know is whether a changing magnetic field will exert a ...
0
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0answers
16 views

Spring constant of a union of springs - Why is it so? [duplicate]

As I was learning about springs, I bumped into a theory saying that if we take one, long spring and divide it (cut) into, let's say, two springs of the same length, their spring constant will be $k = ...
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4answers
114 views

Why the pressure in liquids only depends on the height?

look at this picture : and also look at this one: imagine that the surface area of both is the same and both of them are full of water. My question is that why they both are pressing the beneath ...
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0answers
33 views

Adding multiple torque vectors together to determine resultant torque

I am working in a 2D environment, where there are multiple angular forces (torque) applied at an object. The way I calculated 1 torque "application", was by: ...
2
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4answers
132 views

Is this Coriolis Force explanation simplified?

As air moves from high to low pressure in the northern hemisphere, it is deflected to the right by the Coriolis force They use an example of a merry-go-round, which makes sense intuitively. An ...
0
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1answer
44 views

Does momentum scale linearly with time, assuming a constant nonzero net force, even at relativistic speeds?

I would expect it to, since you'd think the loss of velocity due to relativity would be made up for by the gain in relativistic mass. I'd like this to be confirmed, though. and if so, in whose ...
1
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1answer
76 views

Why a bullet leaves a hole on glass where stone makes scratch?

When we throw a stone it breaks the glass with scratches. But when a bullet hits the glass it leaves a small hole(not always) . I want to know the specific reason behind making hole and scratch.
1
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1answer
20 views

Power needed to raise a bucket at a constant speed by a pulley

This is the last section of this pulley exercise: The bucket in is filled with water so its total mass is now $45$ kg. The bucket is raised at a constant speed of $2.0$ $ms^{-1}$ using an ...
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2answers
32 views

If a block moves on a straight line (no friction) for time $T$ and then along an incline plane, what will the displacement vs. time graph look like?

In my opinion, the graph for the first part of the motion will be a straight line passing thorugh the origin (at the beiginning of motion) and then it will be a falling parabolic curve ( $x$ is ...
1
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3answers
117 views

How does the Electric Field create a force? [closed]

If we have 2 charged particles which are a certain distance away from each other, they either attract of repel due to the electric field created by both of them. But I don't understand the mechanism ...
1
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0answers
39 views

Why we can use partial derivatives to tell if a force is conservative? [duplicate]

Let us, initially, analysis only a two dimension situation. Assume that $F(x,y)$ is a force dependent on the particle position (give by $x,y$) is proposed that if \begin{equation} \frac{\partial \...
0
votes
1answer
49 views

Are all forces given by a field conservative forces?

When teaching us electromagnetism, our professor first introduced us to the concept of "field". Several lessons later, he proved that electric field force is a conservative force. But I think the ...
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2answers
47 views

Simple question about inclined planes

Assuming all surfaces to be frictionless. If the mass of the inclined plane is large enough, could $N$ ever be equal to $mgcos\theta$. Reasons? So far I've come up with: $mgcos\theta - N = ma$ ...
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2answers
209 views

Balancing forces on a liquid [closed]

My reasoning is as follows Atmospheric pressure = $P_{0}$; Spring stretch = $x$; Pressure under top piston = $P$ Balancing forces on top piston $kx + P S_1 = P_0 S_1$ Balancing forces on bottom piston ...
3
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2answers
67 views

Why are upthrust and normal reaction force not the same?

I am currently studying IGCSE Physics, and have the following question: Why aren't upthrust and normal reaction force not the same. I understand that upthrust only occurs in fluids, and normal ...
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1answer
27 views

Why is force negative if PE increases?

I'm looking at the PE vs force graphs for gravity, and it doesn't make sense to me. As potential energy increases (and the object goes higher above the ground), F=-mg. But if I'm raising an object up, ...
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0answers
24 views

Calculating impact force of steel tip darts for soundproofing

I'm trying to soundproof a dartboard by mounting it with silicone gel vibration mounts. I'm having trouble selecting anything though because I need to know what kind of forces I'm trying to mitigate. ...
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0answers
40 views

Newton's third law confusion [duplicate]

If A exerts a force of 200N on B, then by newton's third law, 200N would be exerted on it. Similarly, if B exerts 100N on A, by newton's third law, 100N would be exerted on it. Therefore the net ...
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votes
1answer
77 views

What does $P = Fv$ mean? [closed]

The engine of a car is developing a power of 90kW when it is moving on a horizontal road at a constant speed of 100 km h−1. Estimate the total horizontal force opposing the motion of the car. I ...
1
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2answers
36 views

Centripetal force and friction

Here is the question I need help on: A hemispherical pile of snow with a height of 20 m is piled up. An extreme skier starts at the top of this snowball, and she skies down finding that ...
0
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0answers
34 views

How to calculate maximum magnetic flux density of magnet?

I have some magnets of which I need to calculate the maximum magnetic flux density B. I don't have any dedicated setup to measure the value. Is there any way in which I can measure it by relating it ...
-2
votes
2answers
45 views

Condition for a particle to move on a sphere

Is it possible for a particle of mass $m$ to complete a circular path on a sphere if it starts from the topmost point and no external force acts on it except gravity and frictional force between ...
-1
votes
1answer
40 views

What is the amount of Power required to maintain a flywheel at an angular velocity $\omega$ rad\sec of mass $M$ kg and Radius $R$ m? [closed]

What is the amount of Power required to maintain a flywheel at an angular velocity W rad\sec of mass M kg and Radius R m ?
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0answers
22 views

Will the force acting be doubled? [duplicate]

If me and a man are holding a string, and I apply a force of 100N, the tension in the string would be 100N, and it would exert a 100N force on the man and an equal and opposite force of 100N on me. ...
0
votes
1answer
52 views

Can drag force and lift force be in the same direction in the following case?

In the attached picture, can I say that there is a lift force in the Y-direction, and a drag force too in the same Y-direction? $F_L$ proportional to $V_fx^2$ ? $F_D$ proportional to $V_py^2$ ? Is ...
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votes
0answers
28 views

BASED ON NEWTON'S 3RD LAW [duplicate]

my question is based on newton's 3rd law . An elephant pushes a rabbit with $250 N$ force , then the rabbit should also apply $250 N$ force but the rabbit is only capable to apply $25 N$ force . Why ...
0
votes
1answer
40 views

Force of Electrostatic Attraction between 2 rings

Before someone puts it on 'hold' , this is not a homework question, I doubt you'll find it somewhere as I thought of it. I wish to find force of electrostatic attraction between 2 uniform rings of ...
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3answers
61 views

Is drag force in the direction of particle motion or opposite to motion?

Suppose water is flowing in horizontal direction (positive $x$-direction) and a particle immersed in that water is also moving in the same direction. In this case, is the drag force $F_D$ in the ...
3
votes
3answers
117 views

Is static friction the only force causing a car to move (without sliding)?

A car is moving without sliding means that the friction between wheels and the ground is static friction. This is the force causing an object to move forward, therefore, its direction is the same as ...
0
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1answer
46 views

Thermofluid mechanics inclined plane

As shown in the attacked image, a tank has an inclined wall at an angle of 450 to the horizontal. On this wall, there is a 1m square door that is hinged at A and has a simple latch at B. The distance ...
0
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3answers
72 views

Components of gravity in an inclined plane

The reason the block accelerates down the inclined plane is that the resultant of $N$ and $mg$ acts down the incline. However, why is the force causing the block to accelerate down the incline often ...
3
votes
1answer
52 views

Bent capillary tube

What would happen if I bend a capillary tube and use it as shown in figure? 1.Will the water(or any other adhesive liquid) level remain same as before bending? 2.or it will come up till end? 3.Or ...
1
vote
0answers
12 views

Net force of a falling down people by Resolution of Force. [closed]

From the picture, I want to calculate the Force (F) when people fall down. I searched the internet, but I have no findings. Given that Mass (M) = 75 kg, Gravitational force (G) = 9.81 N. How can I ...
0
votes
1answer
33 views

How to calculate impulse required to move an object vertically upward by given distance [closed]

Suppose I have a stationary object of mass $m$ and I want to apply a momentary force in the vertical direction so that it just reaches the height $h$. So how do I calculate the impulse required in ...
-2
votes
1answer
56 views

Net acceleration of an object if too many forces are acting on it? [closed]

Consider an object thrown upward with a force which is much greater than its weight. Obviously the object will stop after a certain interval of time due to air resistance. But what if there is no air ...
-1
votes
1answer
28 views
-1
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1answer
28 views

Net force equal to mass multiplied by acceleration of centre of mass [closed]

$F=ma$ if $a=0$ then definitely the net force applied will be also zero (0). then, in this case $m=F/a$. If both net force and acceleration(of centre of mass) is equal to zero (0). then, isn't mass ...
3
votes
3answers
42 views

Work done on an object by the internal forces

How is the work done by the internal forces acting in a rigid body zero? Actually I read in a book an example for the same. Let me present that example here. Consider a rigid body having two ...
4
votes
3answers
78 views

How do I find the relation between the accelerations of the ring and the disc (see image)? [closed]

What is the relation between the accelerations of the ring and the disc (see image)? Both the ring and the disc have mass $M$. The ring has a radius $R$ and disc has radius $2R$. They are connected ...
0
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1answer
34 views

Understanding electric potential in the context of gravitational potential?

I'm trying to understand the concept of electric potential and the significance of an electric field being related to the gradient/derivative of an electric potential. I found this question that ...