All Questions
Tagged with free-body-diagram newtonian-mechanics
1,692
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Person holding two persons hanging over the edge and centre of mass inconsistency
Imagine a person holding the leg of the person in front that also holds the person in front of him. (over the edge like in MI4, assume centre of mass of second person with feet still on the floor is ...
- 183
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Mechanics and constraint relation [closed]
Please solve this mechanics problem .
I couldn't derive the relation of extension of cords
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21
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Rope sliding from frictionless surface inconsistency [closed]
Imagine a rope that has a mass lying on a frictionless table and one part of it is hanging over the edge. I know that if there is no friction it does not matter how much of the rope is hanging over ...
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A bird in a container [duplicate]
Suppose there is a bird in a sealed container, and the container is on a scale that measures its weight. The bird is flapping its wings to hover in the middle of the container. If the bird flaps its ...
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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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Why can we treat a ball as a point mass to calculate torque?
A sphere of radius $R$ is supported by a rope attached to a wall as shown in the below figure. The rope makes an angle $\theta$ with respect to the wall. The point where the rope is attached to the ...
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A paradox while explaining the equilibrium of books
An even number of books (say four) are held in the manner shown in the figure. It is obvious that if we apply a large force inwards, we can increase the normal force, and hence the friction which ...
- 489
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Tension of rope over frictionless edge obstructing block
Consider the diagram below. All corners are assumed to have no friction. Is it true that the tension throughout the rope is equal in all sections? The section over the edge of the building, the ...
- 101
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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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When an object is thrown towards the sky it starts to gain potential energy, why?
I didn't think so because when an object is thrown towards the sky it already has kinetic energy and it looses it's energy due to the gravitational force of the earth.
When the object looses all of it'...
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What does $v$ actually represent in pulley problems?
Let us consider the problem of two pulleys with boxes attached to their ends. One pulley is movable, and the other is not. The problem requires us to find a relationship between velocities of these ...
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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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1
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71
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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 ...
- 19
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How Does Hydrostatic Pressure Account for Liquid Layers That Can Mix?
I'm trying to understand how pressure in a homogeneous fluid at a given depth is determined by the weight of the fluid above that point. Specifically, I am confused about how the weight of the liquid ...
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