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primarygun
Dec2-04, 02:41 AM
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?

arildno
Dec2-04, 07:30 AM
"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???

ulli
Dec2-04, 12:32 PM
:confused: :confused:

primarygun
Dec3-04, 02:55 AM
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?