Two blocks of msses 10 kg and 30 kg are placed along a vertical line. The first block is raised through a height of 7 cm. By what distance should the second mass be moved to raise the centre of mass by 1 cm?

Explanation

Two masses `m_1 and m_2` ar kept in a vertical line
`m-1=10kg, m_2=30kg`
The first block is raised through a height of 7 cm.
The centre of mass raised by 1 cm.
`:.1=(m_1y_1+m_2y_2)/(m_1+m_2)`
`=(10xx7+30xxy_2)/40`
`=70+30xxy_2)/40`
`rarr 70+30y_2=40`
`rarr 30y_2=-30`
`rarr y_2=-1`
the 30 kg body should be displaced 1 cm downward in order to raise the centre of mass through 1 cm.