Question 661: Centre of Mass and Rotational Motion

Question

ABC is an equilateral triangle with O as its centre. $${\overrightarrow F _1},{\overrightarrow F _2}$$ and $${\overrightarrow F _3}$$ represent three forces acting along the sides AB, BC and AC respectively. If the total torque about O is zero then magnitude of $${\overrightarrow F _3}$$ is

Accepted Answer

Let x be the distance of centre O of
equilateral triangle from each side.
Total torque about O = 0
$$ \Rightarrow $$ F
1
x + F
2
x Ã¢ÂÂ F
3
x = 0
or F
3
= F
1
+ F
2

Answer

F1 + F2

Answer

F1 $$-$$ F2

Answer

$${{{F_1} + {F_2}} \over 2}$$

Answer

2(F1 + F2)

Centre of Mass and Rotational Motion

ABC is an equilateral triangle with O as its centre. ${\overrightarrow F _1},{\overrightarrow F _2} and {\overrightarrow F _3} represent three forces acting along the sides AB, BC and AC respectively. If the total torque about O is zero then magnitude of {\overrightarrow F _3}$ is

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