In the arrangement shown in the figure M_a\ "and"\ M_b are 2\ "Kg and"\ 1\ "Kg" respectively .Find the acceleration of center of massof both the blocks Neglect friction everywhere . ?

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1 Answer
Aug 2, 2017

See below.

Explanation:

Considering

x_g = (m_ax_a+m_b x_b)/(m_a+m_b) as the system center of mass

we have

ddot x_g = (m_a ddot x_a+m_b ddot x_b)/(m_a+m_b)

For each mass we have

{(T-m_a g = m_a ddot x_a),(T-m_b g = m_b ddot x_b):}

but due to the fact that the rope is inextensible

ddot x_a = -ddot x_b = a and substituting and resolving for a we have

a = ((m_b-m_a)/(m_a+m_b)) g now substituting into the formula for ddot x_g we have

ddot x_g = -((m_a - m_b)/(m_a + m_b))^2g