Achieve a state of static equilibrium

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Colin19
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Homework Statement


If a body is acted upon by clockwise moments of 75 N at 1.25 m
And anticlockwise moments of 50 N at 1.3 m ,
Is it in a state of static equilibrium ?
If not what is required to achieve a state of static equilibrium ?


Homework Equations


sum of all forces on all particles of the system is zero ...


The Attempt at a Solution


Should I increase the 50 N to be 75 N , Then level the distance to get the equilibrium ?
I really don't know What/How to solve this , Please guide me through ,
Your helping efforts are Highly needed and appreciated .
 
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That is one way, but i think the idea is to calculate the torque needed to obtain equilibrium, and since they act from different distances you would write something like:
[itex]\sum\tau = l_1f_1 - l_2f_2 = 0[/itex]
and that is the condition /equation you need to solve it.
 
I don't get these symbols ? more HELP please
Please consider that I know so little, Teach me like a kid
 
is it force x given distance ?
in the question it would be
75 N X 1.25 m
?
 
Yes. The moment about a given point is the size of the force x the perpendicular distance to that point.

What do you know about the sum of the moments of the forces of a system that is in equilibrium?
 
Answer
- No it’s not in a state of static equilibrium,
In order for a body to be in static equilibrium
The vector sum of the forces and torques should be zero
Moments:
Moment = force × distance
Clockwise=
75N × 1.25m = 93.75 Nm .
Anticlockwise=
50N × 1.3m = 65 Nm.
Total moments= 93.75 – 65 = 28.75 N clockwise direction
so clearly it’s not in a state of static equilibrium,
If the perpendicular distance of the anticlockwise moment was changed to 1.875m we would then get
50N x 1.875 = 93.75
75N x 1.25 = 93. 75
We now have it in a state of static equilibrium.