Exploring Newton's Third Law: Rope with a Wheel & Work/Potential Energy

AI Thread Summary
In the discussion about Newton's third law, a scenario involving a rope and a wheel is presented, questioning the reaction force when 50N is applied downward. The conversation shifts to work, with an inquiry about whether the force in the work equation is continuously applied, similar to weight, and if the object would eventually stop. Additionally, a scenario is posed where a man lifts a 100N weight to a height of 10m, questioning why the force exerted remains 100N despite being countered by the weight's gravitational force. The participants seek clarification on these concepts, particularly the implications of continuous force application and the relationship between applied force and gravitational force. Understanding these principles is crucial for grasping the fundamentals of physics related to forces and energy.
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One question related to Newton's third law,
v
t p
u o
u o
It is a rope with a wheel,v.
If 50N is applied from u pulling towards the ground, what's the reaction force?
From o to p ?

Two questions related to work,
I think the force in the equation of work done is continuously applied,like weight, right?
And the object would not stop finally, right?

For the PE, a weight of 100N is lifted up by a man up to a height of 10m.
Why the force applied by the man continuously is 100N?
Isn't 100 N causing no effect on the weight as it is compensated by the mg of the weight, right?
 
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"One question related to Newton's third law,
v
t p
u o
u o
It is a rope with a wheel,v.
"
What does this mean?
 
:confused: :confused:
 
How about these?
Two questions related to work,
I think the force in the equation of work done is continuously applied,like weight, right?
And the object would not stop finally, right?

For the PE, a weight of 100N is lifted up by a man up to a height of 10m.
Why the force applied by the man continuously is 100N?
Isn't 100 N causing no effect on the weight as it is compensated by the mg of the weight, right?
 
Thread 'Collision of a bullet on a rod-string system: query'

Thread 'Collision of a bullet on a rod-string system: query'

In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
View full post »

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