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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2
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3answers
277 views

Would the rotation of a space ship in vacuum slow it down

Firstly , a few disclaimers : English is not my native language so I may use the wrong technical terms. Please notify me and I will correct the question. As a CS major , I've only taken one class ...
0
votes
1answer
116 views

Maximum velocity on Unbanked roads and why should friction be more than centripetal force? [closed]

Why is maximum velocity on unbanked circular road given by $\sqrt{urg}$ where $u$ is coefficient of friction, $r$ is radius of circular track and $g$ is acceleration due to gravity? Why should ...
0
votes
1answer
446 views

Liquid placed in a rotating cylinder

The Question A closed vertical cylinder is filled with an incompressible liquid of mass m completely. The cylinder is now sealed from all sides and rotated about ...
0
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0answers
233 views

How to find force acting on ferromagnetic material when it is placed in external magnetic field?

When we bring magnet towards ferromagnetic material ( like iron nails), then material gets attracted towards magnet. Since there is motion of material, there must be force acting on it. How to find ...
0
votes
2answers
315 views

How does the force between two charges becomes zero?

In case of Coulombs law, $$ F=k\frac{q_1q_2}{d^2} $$ So, if $F=0$, then $q_1q_2$ must be 0. Is this true?
1
vote
1answer
163 views

Large rotation Euler-Bernoulli beam boundary condition

Is given in Wikipedia as $$EI\frac{d^4u}{dx^4}-\frac{3}{2}EA\left(\frac{du}{dx}\right)^2\frac{d^2u}{dx^2} = q(x) ,$$ where $q(x)$ is the transverse load (assuming uniform cross-section and no axial ...
2
votes
1answer
200 views

Rate of acceleration for two hanging masses in two experiments

I conducted an experiment where two masses of different weight were attached by a string and fed through a pulley. The difference between the masses was $0.025\: \mathrm{kg}$. The lighter mass was ...
2
votes
2answers
567 views

How does the Lorentz force work?

How does the Lorentz force work? In the context of a homopolar motor. I am a year 13 student so please keep your answers simple! I am having trouble understanding the Lorentz force; does the magnetic ...
17
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5answers
2k views

How is potential energy actually stored in a steel spring at the atomic level?

Elasticity is one the most intriguing phenomena, wiki gives a summary explanation of what happens in a steel spring: the atomic lattice changes size and shape when forces are applied (energy is ...
6
votes
2answers
260 views

What are fundamental dimensions used to describe the physical universe? [closed]

I have heard that the universe can be explained in terms of the four fundamental forces. I have also heard it can be explained in terms such as space, time, energy, mass or even motion. To further ...
0
votes
2answers
277 views

Who plays the role of centrifugal force in an inertial frame of reference?

It is noteworthy to quote a sentence from my book, It is a misconception among the beginners that centrifugal force acts on a particle in order to make the particle go on a circle. Centrifugal ...
0
votes
1answer
867 views

Physics Forces and Friction [closed]

I'm working on this problem for my college physics class. It has to do with forces and friction and I want to make sure I go about this problem in the right way. I believe my teacher said that this is ...
0
votes
2answers
271 views

Why do you have less control over a bicycle with a broader steer?

I recently had an argument with someone on why a bicycle with a broader steer gives you more control. We both had different answers to this question and neither could convince the other. First a ...
2
votes
1answer
395 views

How to find “Time” from “Force vs. Velocity” graph? [closed]

If I have Velocity on the $y$ axis and force on the $x$ axis how can I calculate the total time it takes to reach 4000 newtons? Is this just a case of integrating the gradient of the line?
0
votes
1answer
592 views

Finding Acceleration of Two Masses in an Ideal Pulley [closed]

I am stuck on this problem: Two masses are connected by a string which goes over an ideal pulley. Block A has a mass of 5kg and can slide along a rough plane inclined 30 degrees to the horizontal. ...
-1
votes
3answers
693 views

Where does the force to stop a constant velocity object come from?

If a ball hits a wall at a constant velocity, it will slow down and eventually come to rest. Since the ball was at constant velocity, it was not accelerating, and so there was no force. Also, the ...
2
votes
0answers
106 views

Force and Energy in robots

There are two similar and hypothetical robots that move with wheels powered by motors, Robot A and Robot B. Robot A has a gear ratio of 3:1 (The gear connected to the motor is three times larger than ...
0
votes
7answers
477 views

Could Galileo ever prove that $g$ is the same for a feather and a hammer?

Do you think he could have possibly found a way to make a feather and a hammer touch ground simultaneously, as they should, according to gravity? Can you make up a device that avoids air resistance? ...
3
votes
1answer
291 views

How would the Sun's gravity affect us if we weren't in orbit?

So since we're in orbit around the sun, we are basically in free-fall. From what I understand, this means that we don't feel the gravity of the Sun like we do the Earth. Just like astronauts on the ...
0
votes
3answers
402 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 ...
4
votes
4answers
1k views

Why doesn't centrifugal force appear on an FBD for a car on a banked track?

Suppose you wish to find the max speed at which a car can travel on a banked curve of radius R and angle theta to the horizontal and coeff. of static friction mu. I don't understand the relevant ...
0
votes
2answers
3k views

The direction of frictional force in smooth rolling motion

I want to ask about the direction of frictional force in smooth rolling motion which means the rolling object doesn't slide on the surface. Here is the first case, the wheel rolls to the right so the ...
1
vote
0answers
75 views

Force if a diver is lifting a pillar out of the water?(High school physics) [closed]

A diver is searching through the remains of an old shipwreck at a depth of 45 m below the surface of the ocean. The diver finds a marble pillar that is approximately 1.7 m x 0.15 m x 0.15 m in ...
1
vote
3answers
434 views

Is linear momentum conserved in an isolated system always?

Consider a isolated system of particles. If no external force acts on this system, the momentum of the system should remain constant. If the isolated system of particles represents living creature....
2
votes
2answers
303 views

How long does force apply?

If you were to throw a ball into the air while standing on earth, it will take some time to grow from zero relative velocity to it's maximum height before the velocity starts to increase again as its ...
3
votes
2answers
187 views

The force of gravity is $F_g=+mg$ or $F_g=-mg$?

I have noticed that in my classical mechanics course and in the textbook I read for it, seem to ignore the gravitational force's position. For example, if we were dealing with a system with a ball of ...
2
votes
1answer
123 views

Is energy affected by forces?

Curious, is any certain form of energy, such as heat, affected by a force? Can you push energy from one place to another?
2
votes
1answer
372 views

Mass, Acceleration, and Force

The Problem: (a) A car of mass m is on an icy driveway inclined at an angle of 20$^{\circ}$, Determine the acceleration of the car, assuming that the incline is frictionless. The questions is ...
1
vote
1answer
785 views

Forces and motion (Newtonian)

A 10 kg monkey climbs up a massless rope that runs over a frictionless tree limb and back down to a 15 kg package on the ground. Part a) What is the magnitude of the least acceleration the monkey must ...
2
votes
2answers
50 views

The time interval of fundamental interactions?

I extract the below text snippet from our text book: Strong interaction is charge independent.The time interval of such a strong interaction is about $10^{-23} sec$ and it's range is approximately ...
0
votes
1answer
239 views

Gravitational force and Electromagnetic force?

I found this interesting note in one of my textbooks, The enormous strength of the electromagnetic force compared to gravity is evident in our daily life. When we hold a book in our hand, we are ...
-1
votes
1answer
114 views

Is there always motion, when force is present? Is all motion vibration?

Even when you are seated in a chair, the chair is pushing up on you and you down on the chair (manifesting in the form of ~650N). While there is no obvious observable motion, is it not possible that ...
0
votes
1answer
99 views

Gravitational work

As far as I know gravitational work is independent from the path of the object, and I have an object that goes up on a inclined plane to a certain height, and than, after the object reaches the edge ...
0
votes
3answers
289 views

Work and free body diagrams

I am a bit confused with how to find work when there is a free body diagram. I am trying to work out this problem, and in it a box is being pulled at a constant speed by a rope at a constant angle ...
0
votes
1answer
1k views

Calculating the acceleration in a multiple pulley system with one mass? [closed]

This sounded really simple to me at first, but how would you calculate acceleration within a multiple pulley system like this one . I understand that $5T = mg \implies T = \frac{mg}{5}$, but what if ...
0
votes
2answers
226 views

Force vs. impulse: what is the math description of their interaction?

In this image there are two forces acting on the same body, and we can decribe them mathematically and geometrically using vectors and the palallelogram rule. NOw, suppose the box (stone, bullet..., $...
2
votes
1answer
475 views

Cart and Fan Problem [closed]

I have this problem : A 2.19-kg cart on a long, level, low-friction track is heading for a small electric fan at 0.21m/s . The fan, which was initially off, is turned on. As the fan speeds up, the ...
2
votes
1answer
267 views

Langevin equations in translational and rotational direction

I want to describe the following system. A bead is connected with a tether. There is a force $\vec{F}_{up}=F_{up}\hat{y}$ that acts on the bead. The tether acts with a force on the bead, this force $...
5
votes
3answers
8k views

Tension of rope. Different Answers?

The tension of a rope in a tug of war with unequal forces is equal to the least force on the rope. Am I right? (If group A pulls the wire with 20 newton leftwards and the group B pulls with 30 newton. ...
3
votes
3answers
360 views

Line integral definition of work clarification

So I am kind of confused about the role of force when calculating work. Specifically, when defining work using a line integral. There is a paragraph in my calculus book that is really throwing me off ...
0
votes
4answers
264 views

A question on force and acceleration

Q 1. Two bodies, $m_1$ and $m_2$, in contact with each other, are under constant acceleration $a$ in the same direction. Find the force exerted by $m_1$ on $m_2$. A similar question with my ...
0
votes
1answer
2k views

Force between two blocks on a friction-less surface [closed]

The question is, A single horizontal force $F$ is applied to a block of mass $M_1$ which is in contact with another block of mass $M_2$ as shown in the figure. The surfaces are ...
0
votes
1answer
136 views

Friction because of Earth's rotation

Is there some force of friction that acts on bodies due to rotation of Earth. We all know earth is an non inertial frame. If there is some frictional force is there some way to prove it. What i mean ...
1
vote
2answers
717 views

Repelling force of magnets

What happens if I take two strong magnets and press their like-poles towards each other - does the repelling force created by them equals the force I'm exerting on them or does the repulsion force ...
1
vote
3answers
111 views

Problem in understanding Newtonian 2nd law

In Resnick, Halliday, Walker s' Principle of Physics , I found this question : Two forces are acting on a block on a frictionless floor. On the left of the block $3~\text{N}$ & on the right of ...
1
vote
4answers
167 views

Can you travel through the air using falling rubble?

As seen below in Dragonball Z, we can see Uub jumping from one piece of rubble to the next to reach Goku in mid air. This kind of scenes are seen often in cartoons, so it made me wonder if physically ...
0
votes
1answer
42 views

two bodies are travelling with equal acceleration

two bodies are travelling with equal acceleration in the same direction and are in contact with each other. What will the force exerted by 1st body on second be? By taking an example of masses 5 and ...
2
votes
2answers
132 views

Force balancing - Newtonian mechanics [duplicate]

If a horse pulls the carriage, the carriage should pull the horse with equal force (Newton's third law), then how does the whole system move? I drew the free body diagram but not yet figured what ...
0
votes
1answer
81 views

Force-carrying particles instead of forces

Are there physical theories in which notions of particle are used without the concept of force? I know about gauge bosons, see: http://en.wikipedia.org/wiki/Force_carrier and http://en.wikipedia.org/...
23
votes
5answers
6k views

Why are a motorcycle's front brakes more effective than back?

I've noticed that when I apply the front brakes on my bike it stops quite quickly. If I apply the back brakes at the same speed, it skids rather than stopping quickly. Why?