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Homework Statement
Homework Equations
Σtorque = 0
Σfx=0
Σfy=0
torque= F r sinθ (θ is the angle between the r and the F)
The Attempt at a Solution
OKay, now i know how to solve this, but it's like i asked myself, how to know if this is a question that i am supposed to use
Σfx=0 and Σfy=0 (Newton's law lesson) and get the answer or to use the Σtorque=0 with Σfx=0, Σfy=0. so i said let me solve this question as if i still didn't take the torque yet, and if i couldn't reach to any answer and have not enough known values , then of course i will have to use the sum of torque= 0 to reach the answer. ( Know that this question can be solved only by the sum of torque=0 without going through the sum of forces).
so i started to find the Σfx=0 forces
and couldn't find only one force which is the x component of the tension force ( Tcos(30) to the west) and what about the other force to the right? is it the N force from the wall or what.
i said maybe it's N force ( not sure), and it's not written here since the torque of this force will be zero because it passes through the pivot point chosen (it's shown near the wall in the figure). so i want to know what is the opposite x force to the east to cancel Tcos(30).
and for y it would be: Σfy=0
Tsin30 = Mg + mg
right?
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