Question

Two masses A and B having mass $m_a$ and $m_b$ respectively, lying in the plane of the fifure shown, are rigidly attached to a shaft which reloves about an axis through O perpedndicualr to the plane of the figure. The radii of rotation of the masses $m_a$ and $m_b$ are $r_a$ and $r_b$, respectively. The angle between lines OA and OB is ${90}^o$. If $m_a=100$kg, $m_b$=20 kg,$r_a$=200 mm and $r_b$=400 mm, then the balance mass to be placed at a radius of 200 mm is kg(round off two decimal places)

Answer 1

Balance mass radius, $R_B=200$ mm
$M_b=?$
$M_B{R}_B=\sqrt{(10\times 100{)}^2+(20\times 400{)}^2}$
$M_B\times 200=8246.211$
$M_B=41.23$ kg