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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Is the weight of the aircraft flying in the sky transferred to the ground?
Is the weight of the aircraft flying in the sky transferred to the ground? Is the weight of people swimming in the pool also transferred to the ground? How can we prove it?
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Given that ice is less dense than water, why doesn't it sit completely atop water (rather than slightly submerged)?
E.g.
If we had a jar of marbles or something else of different densities and shook it, the most dense ones would go to the bottom and the less dense ones to the top.
(Image Source)
If I put a cube of ...
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Principle of physics used in the lift of skateboard
What is the principle of physics used in this popular stunt?
Initially, I thought aerodynamics due to an increase in the angle of attack, but its magnitude is not sufficient to balance the whole body ...
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How does tilting a bike make it turn sharper?
Note that my question is not why do you tilt your bike when on a curve. It's about the reduction in turning radius when one tilts the bike inwards.
Short to-the-point answers are welcome.
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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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Solving the helicopter hanging cable problem through differential analysis
The above problem is taken from the 2014 $F=ma$ contest.
This question generated a great deal of controversy. At least two test takers challenged the
answer, one who even tried to do the experiment. I’...
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Why is bench pressing your bodyweight harder than doing a pushup?
Why does bench pressing your own bodyweight feel so much harder than doing a push-up?
I have my own theories about the weight being distributed over multiple points (like in a push-up) but would ...
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Hanging a hammer from a table and a stick so that its midpoint is outside of the support of the table
I came across this pic on the internet today. At beginning I thought it is just not possible because the centre of mass is way off so gravity will generate torque making the stick and hammer fall. ...
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Does artificial gravity based on centrifugal force stop working if you jump off the ground?
In an answer to another question of mine, concerning gravity, there was a link to a video about the creation of artificial gravity, based on rotation.
The question I have might be silly (or with an ...
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If gravity disappeared, would Newton's third law make everything that was pressed to the ground by gravity get pushed upwards? [closed]
If gravity disappeared, would Newton's third law make everything that was pressed to the ground by gravity get pushed upwards?
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Why do bikes hardly ever skid while braking with the front wheel?
When abruptly braking with the rear wheel on a bike, it tends to skid pretty easily. Doing the same with the front wheel is a very different experience. Instead of skidding, the bike lifts the rear ...
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Can spinning arms really help you balance on the edge of a cliff?
This is how many cartoons depict a character about to fall from the edge of a cliff. You can see movie characters do it. You can also see real people doing it. But does spinning arms like that ...
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Why does twisting a cork make it easier to remove from a bottle?
When we want to remove a cork from a bottle first we turn the cork. Turning in one direction makes it easier to remove in the axial direction.
Does anyone know something more about this?
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Why does a floating object displace more substance than a sunk object? [duplicate]
Consider a box floating on water having a coin on top, now suppose after some time by some external influence, the coin is dropped into water. After doing the calculations, to my surprise, I found ...
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