Questions tagged [free-body-diagram]
A pictorial device which analyzes forces present on any body with the use of vectors. Allows easier grasping of problems involving either objects at equilibrium or in motion. Can be used to predict presence of forces.
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Why is the normal force of a rope on a pulley, not considered while analyzing the free body diagram of pulley?
Suppose an inextensible massless rope is placed on a pulley surface. Obviously there will be a normal force between the pulley and rope, right?
Why is the normal force of rope on the pulley ($N_{...
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How was the reference system taken here?
in this Atwood machine digram
y1 is the amount that m1 gets displaced and y2 is the amount that m2 gets displaced the lecturer then wrote $y1=-y2$ ,
I am trying to understand what did he do to get ...
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What is the amount of force applied on my back while I'm brushing teeth leaning forward?
This is a question I've had for several years but never had the knowledge to calculate myself. Please keep in mind I don't have much background in physics (learned some on middle school I guess...), ...
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Is this how friction is a centripetal force when a car is making a turn? [closed]
I've been wondering why frictional force acts as a centripetal force when a car is turning; my intuition would not lead me to believe it would act perpendicular to velocity, but I think I have at ...
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Why is $mg$ split into components instead of the tension in vertical uniform circular motion?
I am a beginner physics student.
I am trying to prove that the magnitude of the tension varies sinusoidally as an object P travels around the circle or something of that sort. Thus, I am evaluating ...
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Can we have pressure with zero net force on a 2d plane?
From Wikipedia:
Pressure is the force applied perpendicular to the surface of an object per unit area over which that force is distributed.
Suppose we apply 2 equal and opposite forces on a 2d plane ...
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Choosing signs in free body diagrams of subsystems
In an example problem from a book I'm using (David Morin's Introduction to Classical Mechanics with Problems and Solutions), there is a system with a person and a pulley on top of a platform. The ...
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How does surface tension prevent a pin from sinking?
Please explain simply how surface tension in water which as far as I understand is a force pulling the water molecules at the surface towards each other horizontally so how does that prevent a ...
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Internal forces not getting cancelled?
Consider a rope kept on a surface as shown. The ends of the rope are free.
The FBD of this rope given in the book is shown in the following diagram:
Now, consider the Tension forces at points P,Q ...
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Table on inclined plane - normal force
So, I'm struggling to understand how the normal force works in case of the inclined plane. It's obvious for me what happens if the body is, for instance, a block or a cylinder, however, I can't got ...
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Role of the friction force in rolling without slipping
I don’t understand the following concept and I wonder whether any of you could explain it to me.
Let’s consider a wheel rolling without slipping on a horizontal plane. We only consider the moment when ...
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Elasticity and Hooke's law: who is applying the force?
I am currently studying longitudinal vibrations in an elastic beam. However, I am struggling a bit because it is the first time I have done continuum mechanics. More specifically, when isolating an ...
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Pulley-rope tension question
I'm learning mechanics and I don't understand the following (simple, I guess) concept. Here's a pulley-rope system:
The force of tension, as I understand it, is defined as the force exerted on an ...
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How do I calculate frictional forces of an object sliding laterally on a sloped plane?
Game developer here. Most problems about objects sliding down sloped planes with friction are about the object sliding in the natural downward sliding direction of the slope. But how would you ...
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Effective Mass of a moving Pulley system
What is the effective mass of a an accelerating pulley block system?
Consider the setup shown above.
I was trying to find the mass $m$, which would produce the same acceleration of the moving pulley ...
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How can the force acting at the fulcrum of a lever be calculated?
I know how to calculate the force applied to either or both ends of a lever system, but I would like to know how to calculate the force applied over the fulcrum of a lever.
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Tensions in the chains
What is the physics behind this mechanism? What would be the free body diagram be like regarding all the magnitudes of the tension forces present in the chains?
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Is force really considered a push or a pull?
If an object is pushed/pulled at a constant velocity and it doesn't accelerate, is there a net force still being applied to the object? A force is a push/pull so there must be a force, despite there ...
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Maximum no. of books that can be held between two hands without the books falling down? [closed]
The books are stacked horizontally against each other. Each book weighs 1kg(10N).
The coefficient of static friction between hand and book is 0.6 and between book and book is 0.4.
Each hand gives a ...
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How is friction force applied in two block system?
I'm a bit confused about how friction force is applied.
The answer to this question is that the ground applies 75N (kinetic) friction on block B (in the negative direction) and block A applies 5N (...
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Car on circular track problem
A car starts from rest on a horizontal circular road of $190\ \mathrm m$ and gains speed at a uniform rate of $1.2\ \mathrm{m/s^2}$. The coefficient of static friction between the tyres and the road ...
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Tensions in the chains [duplicate]
What is the physics behind this mechanism? What would be the free body diagram be like regarding all the magnitudes of the tension forces present in the chains?
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Pulley system constraint equation
Question on this page: https://www.toppr.com/ask/question/in-the-pulley-system-shown-in-the-figure-the-movable-pulleys-a-b-and-c/
I am confused why the tensions and accelerations in a pully system (...
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How can we know direction of blocks in pulley systems?
How can we find the direction of acceleration in pulley systems so that we can write equation of motion for different parts of the pulley system. Do we have to assume acceleration in some particular ...
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Newton's 3rd law and normal force
There is something I hope you can help me understand...
According to my physics course, when I stand on the surface of earth, the normal force prevents me from "falling down" because it's ...
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Pulley braking question for dummies [closed]
I have a real dumb question. If you have a drum or a pulley that's moving a weight on a wire up and down with constant velocity, then it needs to be stopped within a certain time. What is the ...
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Forces in a staically determinate cantilever Truss, why some experiences compression while others experience tension?
The Redundant Truss Apparatus is constructed with units of basic triangular pin-jointed.
At joint 1, it is fixed firmly due to a support.
At joint 2, it is fixed to a movable support.
Suppose at ...
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Is spring's restoring force action reaction pair?
Let's imagine a spring is attached to a rigid wall.One end is free to move. Now I exert force on that end and make some elongation there. According to Newton's 3rd law, there should be a action ...
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Forces Acting on a Spring
I have consulted other pages on this site with regards to this question, but I have not found a satisfactory answer yet. Take a smooth, horizontal surface, and two blocks, A and B, on the surface. ...
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Is both spring force and friction force are equal in this problem?
I draw a F.B.D of point "A" of a spring(whose spring constant=k and it is massless, elongation form natural length=l). If a person pulls a spring in right direction by making contact at ...
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Why is hookes law not obeyed in vertical circular motion? [closed]
We know that $$T=-kx=-k(R-L)$$where $L$ is the natural length of string, so the tension force must be constant. but in vertical circular motion the tension force is not constant (via analysis of ...
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In this driven double pendulum what would be the position of the proximal arm relative to $x$-axis when stopper loses contact with the peripheral arm?
In the images below I have drawn a double pendulum system with the pivot hub and a stopper A which is imagined to be fixed to some large wall. In both scenarios 1 and 2 the system is initially at ...
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How does the direction of a force applied to a pulley influence the pulley's motion?
Suppose friction is negligible, we want to determine the force F that has to be applied to a pulley (whose radius is $R$) such that the body m has a constant acceleration a, which is given.
What I ...
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Why is this system isolated?
(Image updated for clearance)
Hello,
Assuming that there is no friction anywhere and both box 1 and ramp 2 start at rest, I was wondering why this is an isolated system in terms of momentum ...
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Geometrical stress dependence for a solid cylidrical body subjected to a uniform pressure load?
Suppose a solid, right-circular, cylindrical body has a long axis of length $L$ and end-faces each having a diameter $D$ was placed fully submerged into a fluid having a hydrostatic pressure of $p$, ...
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Does the rope stretch when the pulley of Atwood's machine is accelerated?
Let's say I've an Atwood's machine in which I have two point masses which are different. Now, when I accelerate the pulley, the two masses accelerate at a different rate which can be shown by ...
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Reaction force exerted by pulley's support
Consider an in-extensible string passing over an ideal pulley connected to a block of mass $m$ as shown:
The ends are pulled with a force $F$
Am I correct in saying that the block will experience a ...
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Work done in a pulley system [closed]
We have this pulley system where $m_1 = m_2$ = 1 kg. Considering the rope AB is cut, what would be the work done by the resultant force acting on $m_1$ during 1 second after cutting?
The naive ...
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How come at a certain joint a truss is a zero force member and at another is isn't?
I have a slight confusion regarding zero force members. I'm analyzing a structure and I started at joint E and found that truss GE has a force of 8.4 [kN]. However, if I analyzed it at joint G, I can ...
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Why is tension split evenly between the two rope segments in a two-pulley system?
I understand that the total tension to carry and move the weight would be split between the two segments of the two-pulley system, but I don't see why it would be evenly split between the two. It ...
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Working with ramps and rotational acceleration (friction involved)
Say you have bicycle tire moving with constant velocity.
Since the point of contact with the surface remains stationary, so tire will not slide even on an icy surface.
But if pushed tangentially to it ...
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Why do we always say in spring setup with 2 blocks that when their velocities will be equal it will have maximum elongation/compression?
In this Case the velocites are opposite.Here's my undrestanding:
There are spring setups in which a block having a velocity strikes a spring attached to another block and in that case we find maximum ...
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Eccentrically loaded bolts in which the plane of loading is parallel to the bolt plane
This are eccentrically loaded bolts in which the plane of loading is parallel to the bolt plane.When deriving an equation to this particular problem almost all books start by assuming that $$\frac{F_{...
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Difficulty making sense of falling rod problem
The system is a thin, uniform rod/pencil with perfect symmetry which is released from rest at some small angle $\theta>0$ from the vertical while being on a frictionless surface.
Then there are no ...
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Bending of a cyclist while taking a turn on a horizontal road
I am a high school student and my teacher taught me that a cyclist bend while taking a turn on a horizontal road because if he doesn't bend it then it will rotate due to net torque of friction about ...
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Where does the centripetal force come from? How to calculate?
When a bucket filled with water rotates, the water surface will be parabolic( I mean the water is rotating and the water surface is parabolic). Where does the centripetal force of a particle of water ...
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Picture frame hung by posts in restriction positions
Suppose you have a picture frame (or mirror) and it is held up by a string that goes around two posts which are at coordinates $(x_1, y_1)$ and $(x_2, y_2)$. The corners of the frame are at $(0,0)$ ...
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Derivation of a formula that connects distance moved by the sphere and the flow rate of water
I am a grade 12 student conducting a physics experiment on Bernoulli's principle and the coanda effect. In the experiment set-up shown here, a sphere made of Styrofoam is suspended in the air next to ...
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Resolving a vector into components [closed]
Scenario 1:
There is a block on a horizontal table on which I'm applying a force of 10N.
Scenario 2:
Block B has mass m and block A has mass 3m. Tension in cord CD while B is sliding down A is $\frac{...
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A mass is hanging by a thread from another mass, which starts to fall. What happens and why?
Please consider the following situation (ignoring air friction, and assuming all strings have no mass):
Ball A with mass m1 is hanging from the ceiling by the blue string.
Ball B with mass m2 is ...
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