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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Given Newton's third law, why are things capable of moving?
Given Newton's third law, why is there motion at all? Should not all forces even themselves out, so nothing moves at all?
When I push a table using my finger, the table applies the same force onto my ...
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Why I think tension should be twice the force in a tug of war
I'm going to provide my argument for why I think the tension in a rope should be twice the force exerted on either side of it.
First, let's consider a different example.
Say, there is a person named <...
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When is tension constant in a rope?
Consider a massless rope with pulling forces applied at each end.
How do we decide if tension is constant or not in a rope? Consider a few example scenarios:
For example, if there is a knot in the ...
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A flying fly inside a sealed box on a scale
suppose there is a scale able to measure weight with an uncertainty of $10^{-9}kg$ . On the scale, an airtight plastic chamber is placed. Initially, a fly of mass $10^{-5}kg$ is sitting at the bottom ...
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Why is the tension on both sides of an Atwood machine identical?
The field forces $F_{g1}$ and $F_{g2}$ push down on Block 1 and Block 2, respectivley, where
$$F_{g1}=m_1g$$$$F_{g2}=m_2g$$
Since the pully system reverses the direction of each force, wouldn't the ...
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Bird flying in an open or a closed cage
Assume that you are holding a cage containing a bird. Do you have to make less effort if the bird flies from its position in the cage and manages to stay in the middle without touching the walls of ...
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Rolling resistance and static friction
I am a bit confused about the relation between rolling resistance and static friction.
I have often heard that it is the static friction that lets the wheel roll. Consider the following two cases:
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If Newton's third law is true, why can we sink in sand? [duplicate]
Newton's third law of motion states that every action has an equal and opposite reaction. That is the reason we do not sink into the earth, because when our weight exerts a force on the earth it also ...
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Can you lift a basket up while standing inside it? [closed]
Suppose you stand in a basket and you try to pull the handles of the basket. Will you be able to lift the basket from ground?
Similarly, Baron Münchhausen allegedly pulled himself and the horse on ...
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Tension in an Atwoods machine conceptual?
Assuming $T_1$ is the force that acts on box $1$ and $T_2$ is the force that acts on box $2$.
Exactly what causes the Tension? Why does $T_1 = T_2$?
The problem is we are told to memorize that $T_1 =...
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Why does friction cause a car to turn?
I've had a lot of difficulty conceptually understanding the physics of how a car turns on an unbanked curve, so I'm hoping you could help me out. When a car is moving in uniform circular motion, we ...
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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 ...
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Why does the friction act on the inward direction when a car makes a turn on a level road?
I tried looking this question up online but am left a little confused with all the answers, and the diagrams.
When a tire of a car negotiates a turn in the road, there exists friction which is ...
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Why is tension in a rope the same at every point?
So, I had this lecture where it was explained that if the pulley is friction-less, then the tension on any point of the rope is going to be same.
I can understand the friction-less part, as pulley is ...
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Watching something fall into a black hole from far away
I am observing (theoretically) an object falling into a black hole from a safe distance away. My understanding is that from far away it appears as if the body will asymptotically approach the event ...
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