All Questions
Tagged with free-body-diagram forces
1,316
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Some questions regarding a pulley [closed]
Please have a look at the following diagram sketched by my Professor. The points $P_1$ and $P_2$ have mass $m_1$ and $m_2$ respectively . The pulley is frictionless and it is represented by a ...
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Condition for a car moving with a constant velocity [closed]
I seek your help with this simple yet confusing problem. The question says:
A car is moving with a constant velocity 10m/s. Which one is correct?
No force is acting on the car
The force applied by ...
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Is there any phenomenon where opposite reaction (Newton's 3rd Law) is not fulfilled?
I'm wondering if there is any case in nature/physics where it has been observed "where there is an action, there is not necessarily an exact equal and opposite reaction".
Or is there some ...
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Why does the counterweight actually go up?
So, let's consider a simple ideal pulley system where there's a weight to be pulled, and a counterweight on the other side
According to my understanding (feel free to nitpick), there's a restoring ...
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Statics problem from classical mechanics
I was solving David Morin's book on classical mechanics.
In the solution for the second part of the "a" part of the question, why is the normal force defined as $Ndθ$ and not just $N$? Is ...
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Why do objects slow down when they hit the ground? [closed]
Say you drop an object on the ground. For the purpose of this question, I am just focusing on the slowing down of the object, not if it rebounds. I was just wondering which of the two reasons explains ...
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Determining Tension in a Massless String Under Various Configurations: Straight, Over a Pulley, and Around a Fixed Nail
If a massless string is stretched by applying extensive forces of magnitude
𝑥 on both sides, a tension
𝑇 is developed at every point of the string. If the same massless string is placed over a ...
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How does a vehicle's brake affect the friction between the vehicle and ground?
When brakes are activated in a vehicle it decelerates. Analysing its motion, there can be only one force that can be responsible for it: the friction between the car and the ground.
So does braking ...
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Problem with internal forces in spring following Hooke´s law
When looking at Hooke's law for the entire spring the force is $kx$.
But what happens when analyzing segments of the spring in order to look at the internal forces?
Imagine a spring of length $x$ that ...
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Is the work I do on the object always equal in magnitude but opposite in sign to the work the object does on me?
According to the definition of work, the work I do on an object is equal to the force I apply to the object multiplied by the distance the object moves. By Newton's third law, the reaction force (F21) ...
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Two weighing scales compressed inside a solid frame
Two weighing scales are placed on top of each other at the bottom of a solid enclosed frame.
At the top of the frame a linear actuator is attached.
The linear actuator can extend and press down upon ...
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2
answers
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How would I calculate the force of friction between an RC car and a carpet?
I'm working on a physics project where I aim to demonstrate how different surfaces impact the velocity and acceleration of an RC car due to friction. How can I calculate the coefficient of friction ...
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How does this tensegrity table work?
I have assembled below a desk toy which seems to defy laws of physics at first glance (objects can be placed on top of it up to a certain limit, since it is already under strain).
The toy is in fact ...
- 1,410
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Question about Newton third law especially the reactive force [closed]
Sorry for not giving much elaboration , here is a more detailed question,I have a confusion with the reactive force in dynamic cases (not in statics). Imagine there is a box and a person (both have ...
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Why is work done by normal force 0 here?
In solving this problem from Kleppner and Kolenkow, the (total) work done by the reaction force b/w the cube and the large block is taken to be 0 and I cannot seem to rationalise this.
Clearly, the &...
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