CameraIcon
CameraIcon
SearchIcon
MyQuestionIcon


Question

A right triangular plate ABC of mass $$m$$ is free to rotate in the vertical plane about a fixed horizontal axis through A. It is supported by a string such that the side AB is horizontal. The reaction at the support A  is :
126887_8114120983e147889bdb059da489712e.png


A
mg3
loader
B
2mg3
loader
C
mg2
loader
D
mg
loader

Solution

The correct option is C $$ \dfrac {2mg}{3} $$
The distance of Centre Of Mass of given right angled triangle is $$\dfrac{2L}{3}$$ along BA and $$\dfrac{L}{3}$$ along AC from the point B.
Force of magnitude $$mg$$ is acting downwards at its COM.
Moment balance around B gives:
$$mg(\dfrac{2L}{3})-{ F }_{ A }(L)=0$$  
(Moment= $$\overrightarrow { r } \times \overrightarrow { F } =\quad rFsin(\theta )=F(rsin(\theta ))=F{ r }_{ \bot  }$$)
$$\therefore { F }_{ A } = \dfrac { 2 }{ 3 } mg$$

Physics

Suggest Corrections
thumbs-up
 
0


similar_icon
Similar questions
View More


similar_icon
People also searched for
View More



footer-image