A rectangular plank os mass 'm_1' and height 'a' is on a horizontal surface. On the top of it another rectangular plank of mass 'm_2' and height 'b' is placed. The potential energy of the system is,

A rectangular plank os mass 'm_1' and height 'a' is on a horizontal su

1.	A rectangular plank os mass 'm_1' and height 'a' is on a horizontal surface. On the top of it another rectangular plank of mass 'm_2' and height 'b' is placed. The potential energy of the system is,
Answer» `(m_(1)+m_(2)) ((a+b))/(2)G` `[(m_(1)+m_(2))/(2)a+m_(2) (b)/(2)]g` `[((m_1)/(2)+m_(2))a+m_(2)(b)/(2)]g` `[((m_1)/(2)+m_(2))a+m_(1)(b)/(2)]g` ANSWER :C